UPDATE: Jersey City shooting: How it unfolded

UPDATE: Police officer fatally shot in Jersey City identified as 40-year-old veteran detective

A shooting in Jersey City left multiple people dead, including a police officer, following an hours-long standoff at a kosher supermarket Tuesday afternoon.

Two suspects and three civilians are dead in addition to the police officer, Joseph Seals, a 40-year-old married father of several children.

The shooting is not believed to have been a terrorism attack.

“We have no inkling what the motive was yet,” Jersey City Police Chief Michael Kelly said at a Tuesday evening press conference. "Our officers were under fire for hours.

Kelly said the civilians killed inside the store were killed by the suspects. “We think this was all bad guy fire," he said.

Here’s what we know about the incident:

The gunfire began at about 12:30 p.m. in Bayview Cemetery, where Seals was conducting an investigation. A source with knowledge of the investigation said he was shot once in the back of the head and died at a hospital.

From there, the two suspects traveled to JC Kosher Supermarket on Martin Luther King Drive at Bidwell Avenue. There is a yeshiva and a synagogue on the street as well as a Catholic school.

The arrived in a U-Haul van, dressed in black and carrying long guns into the store, where they opened fire. For several hours, gunfire could be heard coming from the store.

Several Jersey City schools were put on lockdown, but all students and staff were safe, officials said. Public schools began to dismiss children at 4:15 p.m.

At about 4 p.m., SWAT teams entered the building and found five dead bodies, two suspected gunmen and three civilians.

Gov. Phil Murphy traveled to Jersey City later in the evening and met with police officers and city officials.

"We mourn the loss of a brave member of the Jersey City police force. He gave his life in the line of duty,” the governor said.

“This was an incredibly tough day for Jersey City,” Murphy said.

Amanda Hoover can be reached at ahoover@njadvancemedia.com. Follow her on Twitter @amandahoovernj. Find NJ.com on Facebook.

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