NEW YORK (CBSNewYork) -- New York has become one of the busiest cruise ports in North America, with over a million passengers departing from the harbor each year.
That also makes the area one of the prime targets for those with bad intentions.
In the predawn hours recently, a Norwegian Gem cruise ship was making its way back to New York after ten days at sea. Unbeknownst to the 2,000 plus passengers on board, the ship was under surveillance and being swept for a dirty bomb before it came inside city limits.
As CBS2's Maurice DuBois reported, hundreds of cruise ships travel in and out of the Port of New York and New Jersey every year as they return from foreign ports of call.
It's up to a unit within the NYPD's Counter-Terrorism Division to escort the ships in safely and without incident.
"Just this morning, there was an attack on a Saudi Arabian frigate in the Red Sea, and it was a suicide attack," Dan Richards said.
Richards is the chief executive officer of Global Rescue -- a company that provides crisis response and evacuation options to travelers.
Despite few incidents to date, terrorism with respect to cruise ships is not unlikely.
"We know that ISIS and other terrorist organizations are planning these kinds of operations," Richards said.
"That's why we're out here. We want to be as proactive as we can," added NYPD Sgt. Harold Salters.
Salters and his team take to the water day and night looking for potential waterborne attacks like the one launched against the USS Cole in 2000.
"We're concerned about an explosive laden vessel. Some sort of possible hijacking scenario," Richards said.
Cruise ships aren't the only source of concern.
New York Harbor is also packed with oil tankers, cargo freighters, and passenger ferries -- which all fall under the supervisions of Salters' elite group.
Boat pilot Detective Michael Delaney said they also use sonar to scan the piers daily.
"We'd be able to scan the pier and see if there's anything below the surface of the water, and overlay the images to see if there is anything there today that wasn't a few days ago," Det. Delaney said.
While all of these measures may not be at the top of the minds of cruise ship passengers, now that they know about them, they said they certainly appreciate them.
"That makes me feel very much secure," one passenger said.
Also on board the 55 foot twin boats; heavy weapons that the NYPD wouldn't show on camera, but can stop a small vessel in its tracks.
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