The following script is from "The Greatest Escape" which aired on September 27, 2015. Bill Whitaker is the correspondent. Howard L. Rosenberg, producer.
By now, you've probably heard of one of the greatest prison breaks of all time. It happened last July. Joaquin Guzman, known by his Spanish nickname, "El Chapo" or Shorty, is one of the most notorious and violent drug lords in the world. He was a high-value captive, he had broken out of prison before. This time, he was locked away in a maximum security penitentiary, the tightest prison in Mexico.
And yet he got away -- and even more stunning -- he did so through a mile-long escape tunnel that opened up right into his shower stall, the only corner of his tiny cell security cameras couldn't see.
Even those who caught him last year, were shocked by the escape.
Jim Dinkins: Gets arrested for the second time, knowing that he's escaped once before. Goes to prison and is still able to escape a second time. I mean that's something like no other criminal in history that you'll be able to find.
Until he retired last year, Jim Dinkins was head of Homeland Security investigations. He was part of the international manhunt for "El Chapo" for more than a decade.
Jim Dinkins: You know, he was literally in a well-fortified, constructed prison designed to prevent such an escape.
Bill Whitaker: The maximum-security prison in Mexico?
Jim Dinkins: Yes. Designed to penetrate people from coming from air and coming from land. But they didn't anticipate him coming from underground.
So, that's exactly what he did. Almost from the moment he was delivered here to Altiplano prison in February 2014, a construction crew from his Sinaloa cartel began digging a tunnel to free him.
The walls here are as much as three feet thick. The airspace above is restricted. Cell phones, prison officials say, they're jammed for miles around. But none of that made a difference.
From almost a mile away, inside this hastily built cinder block structure in a farmer's field, Chapo's men dug down about three stories and then burrowed 4,921 feet straight toward Altiplano.
A massive construction project right outside the prison might have masked the noise of the underground activity.
The tunnel went under the prison wall and beneath the plumbing and, with pinpoint accuracy, it emerged directly into the shower stall of Guzman's ground level cell.
Jim Dinkins: It's very difficult to navigate underground. This tunnel, I believe, went from point A to point B with only minor deviations, if any. And that is an engineering marvel in and of itself.
Bill Whitaker: How difficult is that?
Jim Dinkins: It's very, very difficult. But I'm sure, when the boss is behind prison, you put your best team and your best foot forward. And they apparently did.
At 8:52 the night of Saturday, July 11th, El Chapo ducks into the shower stall, behind a privacy wall -- the only spot in the five by six-foot cell hidden from security cameras and then he disappears.
He climbed down into the tunnel and climbed atop a motorcycle especially rigged on rail tracks to speed him to freedom. By the time the alarm sounded and a search began, Guzman had vanished into the night.
When Mexican agents located the cinder block structure where the escape tunnel began, the construction crew also was long gone, leaving behind the tools they had used for the project -- a generator, emergency oxygen tanks, a disk saw and car batteries.
Bill Whitaker: What was your reaction when you heard that El Chapo had escaped again?
Chuck Rosenberg: Disappointed. Not shocked.
Chuck Rosenberg is head of the U.S. Drug Enforcement Administration.
Bill Whitaker: He was in a maximum-security prison.
Chuck Rosenberg: He had escaped previously in 2001. So it had happened before. We knew, we knew he intended to do it again.
Bill Whitaker: You knew he was planning to do it again?
Chuck Rosenberg: We knew that he and his folks back in Sinaloa wanted to break him out. We had general chatter, maybe a year or so before he actually broke out a second time, about what they hoped to do. But there was nothing in that information we had about tunnels.
Jim Dinkins: You know, he's a notorious tunnel manufacturer and, and-
Bill Whitaker: The tunnel king?
Jim Dinkins: The tunnel king. You know, he's responsible for more sophisticated tunnels than I think any other person in the history of drug trafficking in Mexico. And so, it's somewhat ironic that he was able to escape using one of the techniques that he really perfected over the last, you know, decade plus.
Ironic, but not terribly surprising. During the last manhunt for El Chapo, his pursuers discovered this...
Bill Whitaker: The tub. Look at this.
A tunnel entrance also concealed in the plumbing, in this case, beneath the tub.
Bill Whitaker: That's amazing.
Chapo devised ingenious smuggling methods. He packed drugs into fake cucumbers and bananas and mixed them in with shipments of real produce. But the thing he worked hardest on was making sure he could always get away. Guzman was the first Mexican drug trafficker to hire architects and mining engineers to build elaborate super-tunnels, complete with ventilation systems, electricity and railways, to ferry drugs under the U.S.-Mexico border.
Mexican authorities led us to a tunnel they found unfinished and just short of the border fence in Tijuana.
Bill Whitaker: This tunnel was discovered just a couple of weeks after El Chapo's great escape. His cartel wasn't just focused on building his escape tunnel, they continued building these drug tunnels at the same time.
This border between San Diego and Tijuana, is one of the busiest international commercial zones in the world. You'll see a steady stream of trucks passing north and south. What you can't see is that beneath one four-mile stretch of this border, it's crisscrossed with dozens of smuggling tunnels.
Bill Whitaker: Why? Because this industrial part of Tijuana is right across the fence from acres and acres of warehouses in the U.S. Drug smugglers dig down inside a building over here, pop up inside a warehouse in the U.S. just a couple of hundred yards away.
This is where El Chapo's Sinaloa cartel honed its tunneling technique.
Bill Whitaker: So when did El Chapo first start digging tunnels here in this area?
Joe Dimeglio: On record, we have the first tunnel was in 2010.
Joe Dimeglio is the chief of the San Diego Tunnel Task Force made up of agents from Homeland Security, the Border Patrol and DEA. The task force was established to respond to what the government deems a threat to national security.
Joe Dimeglio: And down this road, there's been multiple tunnels found in warehouses here.
Bill Whitaker: How far is this from the border?
Joe Dimeglio: This is probably about like 1,400 feet.
Most tunnels are twice that length.
Bill Whitaker: What makes this area so appealing to them?
Joe Dimeglio: Just the infrastructure on both sides of the border, in Otay Mesa and in Tijuana. You have all the commercial businesses there, import, export and just the vast amount of warehouses there that are doing legitimate business. And it's easy to conceal an illegitimate business within those warehouses and it's like looking for a needle in a haystack.
Bill Whitaker: How much does it cost them to build one of these tunnels?
Joe Dimeglio: We've estimated it costs the cartel anywhere between a million to two million dollars. If they have one successful push through of narcotics they've paid for that tunnel and then some.
Bill Whitaker: One load gets through?
Joe Dimeglio: One load. Not just, you know, one kilo. We're talking, you know, tons of narcotics going through.
A load of marijuana could be worth as much as five to six million dollars. Smugglers use the tunnels primarily to move marijuana because it's too bulky, too smelly, too easy to detect to transport over land. Dimeglio's team took us down into one of El Chapo's now-closed subterranean passageways. They are dug through the clay-like soil with picks, shovels and small power tools.
Joe Dimeglio: You can see the spade marks from the air hammer drill on the ceiling. Going across and you see how they worked their way through the tunnel here as they were constructing it. You have rails, the rail system, the rail cart, the lighting, the ventilation. But it's the concealment method that' they've changed, and became more sophisticated.
Bill Whitaker: More elaborate, harder to find?
Joe Dimeglio: Exactly.
Bill Whitaker: So, what are they putting it under up on top?
Joe Dimeglio: This specific entry point for this tunnel was a bathroom floor that was on a hydraulic lift. So the lift actually lowered into another room which was 30 feet below ground.
The task force uses this ground-penetrating radar to try and find hidden entrances to tunnels. But it is only effective down to 10 feet below the surface. The tunnels themselves are so deep, some as much as 90 feet underground. The task force has found no technology that can detect them, not satellites, sonar or radar.
So, how do they find them?
Jim Dinkins: It was good old-fashioned police work that led to those tunnels being discovered.
Bill Whitaker: So, you get a tip off from an informant? Or you see somebody acting suspiciously?
Jim Dinkins: Yes, I mean, some of 'em are just as, as easy as having a neighbor who calls in a nearby warehouse that says, "I hear something underneath my floor and I don't know what it is."
Bill Whitaker: The tunnel that El Chapo's cartel built to break him out of prison, is there anything comparable to that here?
Jim Dinkins: One of my guys actually went down there from the task force and actually walked in that tunnel and observed it. And he came back and I asked him, "So what did you think?" He goes, "It's no different than what we see here. It's exactly the same..."
Bill Whitaker: So they learned it here?
Jim Dinkins: They learned it here. You know mastering every step that they go, every tunnel that they build they learn from.
Along the way, El Chapo -- named to Forbes Magazine's list of billionaires -- also learned his vast riches meant almost anything could be had for a price, possibly even his freedom. DEA Chief Chuck Rosenberg says he was disgusted by El Chapo's prison break.
Bill Whitaker: A tunnel right under the maximum-security prison and up into his cell...
Chuck Rosenberg: Up into his shower stall.
Bill Whitaker: How does that happen?
Chuck Rosenberg: We work with our Mexican counterparts all the time on cases big and small. There's lots and lots and lots of good people down there, men and women who are with us in this. There's also a degree of corruption down there that is disappointing, stunning. Pick your adjective. That's how it happens.
Bill Whitaker: How high up do his tentacles of corruption and bribes-- how high up do they reach?
Chuck Rosenberg: I don't know specifically how high up they reach. My sense is that they're both broad and deep. That they go throughout the Mexican government.
U.S. law enforcement officials knew they had a reliable partner in the Mexican marines the last time they hunted El Chapo. We watched one of their training exercises last year and joined them on patrol in Sinaloa, a mountainous state along Mexico's Pacific Coast, where the cartel still rules.
Bill Whitaker: This is Culiacan, the capital of Sinaloa, this is El Chapo's home turf.
El Chapo had seven safe houses here, all connected by tunnels. In February 2014, the marines and Mexican federal agents began rounding up Chapo's henchmen. They led authorities to this nondescript house in the midst of a middle-class neighborhood. It was a fortress, the marines had to ram their way through a reinforced steel door.
[Bill Whitaker: It took you eight minutes to open the door?
Lobo: Si. Ocho minutos.]
When they got inside, El Chapo was nowhere to be found. But they did find the escape hatch beneath the tub, which led to a labyrinth of interlocking passageways between safe houses and the sewer system of Culiacan.
Bill Whitaker: While Marines were battering down the front door, they say Guzman, startled, barefoot and in his underwear, clambered down these stairs and escaped through this tunnel with his bodyguard and two women.
Even though they had a 10 minute head start, the marines told us they could hear the fugitives splashing through the water. But they were too far ahead to catch. When the marines emerged from this spillway by the river, El Chapo was gone.
Chapo and his wife -- a one time beauty queen -- their twin toddlers, a nanny, a cook and his most trusted bodyguard were desperately trying to shake the marines off their trail. They ditched their phones and got new numbers.
Five days later, American agents traced the new phone of Chapo's bodyguard to the resort city of Mazatlan, 136 miles away, and to this beachfront building. They shared that intelligence with the Mexicans.
At exactly 6:40 a.m. on February 22, 2014, the marines crashed through the door of number 401.
The marines took Guzman into custody. He was fingerprinted and examined for distinguishing marks and scars. He was also photographed and then, after a short helicopter flight, delivered to the gates of Altiplano, an impregnable penitentiary, or so the Mexicans claimed.
Bill Whitaker: It seems to me that for somebody to break out of a maximum-security prison that there had to be help from the inside.
Chuck Rosenberg: Logically, there had to be some sort of help. Had to be.
Bill Whitaker: Had to be blueprints and schematics...
Chuck Rosenberg:: Yeah unless they just tunneled up and got very luck and hit his shower stall. You bet they would have needed something. There's no question in my mind that he had help.
At the time of El Chapo's prison break, the U.S. government was pressing Mexico to extradite him, send him to trial here.
Bill Whitaker: Where was the extradition process when he escaped?
Chuck Rosenberg: We had made our request. They knew of it. They want to prosecute a Mexican who committed crimes in Mexico in their country. It makes perfect sense. The reason we ask for extradition is because his crimes have so grievously injured communities around the United States. And we were concerned that he would do just what he did, escape justice in Mexico. That wouldn't happen here.
Guzman's latest, daring getaway has only magnified the myth of a criminal mastermind who could outsmart all of his pursuers.
In Culiacan, he's a bona fide folk hero. His admirers celebrate his exploits singing that "he laughs at the law." There have been reported sightings of him across Mexico and Latin America. There are social media and blog posts purporting to show him in an airplane or sipping beer at a café. El Chapo also popped up in the U.S. presidential race -- supposedly feuding on Twitter with Donald Trump.
U.S. and Mexican authorities told us, none of those things is true.
Bill Whitaker: Do you have any idea where he is now?
Chuck Rosenberg: No.
Bill Whitaker: You think he would return home to Sinaloa?
Chuck Rosenberg: I don't want to guess. We got him twice. I bet we'll get him again.
Bill Whitaker: You do?
Chuck Rosenberg: I do.
Bill Whitaker: You're confident you'll get him again?
Chuck Rosenberg: I'm reasonably confident we'll get him again.
Jim Dinkins: I am not very confident that we'll ever catch him again.
Bill Whitaker: Why is that?
Jim Dinkins: Because when you go after Chapo, it's not like going after and arresting your local drug dealer or local criminal. This is somebody you have to bring in a whole team and Army, literally, of soldiers and military folks and police officers to go after him and secure him. This is a big operation to go after somebody like Chapo. And it took months, months and years and years to do that once before.
Bill Whitaker: Do you think he learned from the past what you're going to do and what he shouldn't do?
Jim Dinkins: Absolutely. I think he, we've got a smarter Chapo that's out on the street today.
To help Mexico in the manhunt, the U.S. government is once again providing intelligence and equipment and a $5 million reward.