JERSEY CITY, N.J. (CBSNewYork) -- Authorities have identified the shooters behind Tuesday's attack on a Jewish market in Jersey City.
Characterized as targeted, the attack resulted in an hours-long shootout that left six people dead, including a police detective.
Authorities also revealed the suspects were found with a pipe bomb.
"It was a viable device," FBI Special Agent in Charge Gregory Ehrie said during a press conference on Wednesday.
Web Extra: New Jersey Officials Give Briefing On Jersey City Shooting:
"It was a targeted attack on the Jewish kosher deli," Mayor Steven Fulop said. "We could see the van move through Jersey City streets slowly. The perpetrators stopped in front of there, calmly opened the door with two long rifles -- him and the other perpetrator -- and began firing from the street into the facility."
"There were multiple other people on the street, so there were many other targets available to them that they bypassed to attack that place. So it was clear that this was their target and they intended to harm people inside," Jersey City Public Safety Director James Shea added.
New Jersey Gov. Phil Murphy condemned the attack.
"One thing must be made perfectly clear. An attack on our Jewish community, or for that matter on any community in what is by many measures the most diverse state in the United States of America, and whether that attack may be here in Jersey City or anywhere in our state, that attack is an attack against all nine million of us who are proud to call ourselves New Jerseyans, period," Murphy said.
State Attorney General Gurbir Grewal identified the suspects as David N. Anderson, 47, and Francine Graham, 50, adding they were "prime suspects" in the killing of an Uber driver in Bayonne over the weekend. On Wednesday, FBI agents were seen at Graham's address in Elizabethport, where neighbors didn't seem to know much about her, CBS2's Alice Gainer reported.
"As we speak right now we are working to learn more about the shooters' motivations, and whether anyone besides the two gunmen may have been involved," Grewal said. "We know there is significant speculation about the shooters' motives. We're not in the position at this time to say definitively why the suspects decided to stop in front of the supermarket and begin firing immediately."
Anderson parked a U-Haul van directly across the street from the JC Kosher Supermarket, got out of the van with a rifle and started shooting. Graham followed him into the store, Grewal said.
In the store, they killed three of the four civilians they encountered, Grewal said. They were identified Mindel Ferencz, 32, Douglas Miguel Rodriguez, 49, and Moshe Deutsch, 24.
"Our belief is that they were killed almost immediately on the two suspects entering the location," Grewal said.
The survivor escaped the store and his name has not been released.
Watch: Jersey City Mayor Steven Fulop On Deadly Shootout
Fulop said two officers in the area heard the gunfire and rushed to the store, trapping the suspects inside. Both officers suffered gunshots wounds -- one hit in the shoulder, one in the body -- but were hospitalized and have since been released.
"Had they not been there in that location, more than likely more people would have died," Fulop said. "The reason that those perpetrators seemed to be inside of that deli and not able to move potentially to the school or to inflict more harm was because the police responded immediately and returned fire."
PHOTO GALLERY: Scenes From Jersey City's Deadly Shootout
"I believe that streets were filled with people and the schools surrounding were filled with people -- with the amount of ammunition they had, we have to assume they would have continued attacking human beings, if we hadn't been there," Shea added.
The violence began around 12:30 p.m. at Bay View Cemetery off Garfield Avenue, where officers confronted two suspicious people. Det. Joseph Seals, a veteran officer known for taking guns off the street, was shot and killed. Police said the suspects drove off in a stolen U-Haul van to the kosher grocery store on Martin Luther King Boulevard.
Simeon Jackson recorded video of the shootout from his porch. The sound of the gunshots is very clear in the video because his home is so close to the grocery.
COMPLETE COVERAGE: More From Reporters & Witnesses On Scene
First responders swarmed the scene, along with drones and helicopters in the air. People watched it unfold as the residential neighborhood turned into a combat zone.
Grewal said authorities plan to release footage of the incident.
Watch: Mayor Steven Fulop Shares Update On Shooting Investigation (4 p.m.)
Anyone with any additional information about the incident is asked to call authorities at (609) 963-6900.
"Rapid fire, nonstop for about three hours. Gunshots, different kind of gun shots, loud, bang, just out of control," Jackson said. "Like I was in a war zone."
Watch: Jersey City Police Chief Michael Kelly On Deadly Shootout
A hospital and nearby schools were put on lockdown for hours.
"They locked us down until 4 o'clock," said Jackie Covington. "I was so nervous. I'm still nervous. Even this morning, my stomach is like, ugh."
When it was all over, six people were dead -- Det. Seals and the five people found inside the store.
The mayor said there will be an increased presence of police in the area, but there's no indication of any further threats. Officials said it could take weeks, even months, to investigate the extensive crime scene.
A community healing service is set for Wednesday night at Temple Beth-El.
JERSEY CITY SHOOTING COMPLETE COVERAGE
- Attackers Identified, Considered Prime Suspects In Recent Killing Of Uber Driver In Bayonne
- Det. Seals Remembered As A 'Cop's Cop'
- CBS2 Journalists Recount Fear Of Being In Harm's Way
- Victims Identified As Pioneering Mother, Food Drive Organizer
- Anti-Defamation League Talks On Fear Gripping Jewish Community
- Public Schools Operating With Delayed Opening After Lockdown
- Barrage Of Gunfire Heard In Jersey City As Police Move On Shooting Suspects
- Photos: Scenes From Jersey City's Deadly Shootout
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