He was a longtime member of the Jersey City Police Department, often working the streets as an undercover officer.

On Tuesday, Joseph Seals, 40, was shot dead doing his job.

A source with knowledge of the investigation said he was shot once in the back of the head, behind the ear, during an encounter with armed gunmen in a stolen van. He later died at a hospital. Two other officers were shot, but were treated and released, in the furious gun battle on the streets of Jersey City that followed.

Seals, who lived in North Arlington, grew up in Bayonne and went to Bayonne High School, becoming a cop at the age of 22, according to state pension data. He was married and the father of five children.

Police Chief Michael Kelly said Seals worked in one of the busiest precincts in the state, marked by a high volume of crime.

“Dozens and dozens of handguns he’s responsible for removing from the street,” he said.

Seals frequently worked in plainclothes and was assigned to a unit called Cease Fire.

In one Christmas Eve incident in 2008 in which he was later cited for heroism, he and a partner climbed a fire escape and burst through a window to nab a suspect who had broken into a 41-year-old woman’s apartment and attempted to sexually assault her while she was on the phone with police. The suspect attacked the two officers, kicking and punching them, police said, until he was wrestled to the ground.

In 2010, he and a partner also working in plainclothes arrested a suspect in four robberies after recognizing him from mugshots.

In November 2017, Seals was promoted to detective in a City Hall ceremony that saw 20 officers promoted to sergeants, 10 sergeants were promoted to lieutenants and 14 officers promoted to detective.

At his two-story home on a quiet suburban block in North Arlington on Tuesday evening, Seals’ home was decorated for Christmas, with three blow-up snowmen blinking to the tune of Jingle Bells. A projector cast red-and-green lights on the front facade of the home. Family photos were prominent in a sunroom that could be seen from the street. A small North Arlington Vikings Soccer flag was planted in the front lawn.

Det. Joseph Seals (l.), at North Arlington’s trunk or treat behind borough hall this past Halloween, in a photo provided by North Arlington Mayor Daniel H. Pronti.Courtesy of Daniel H. Pronti

Neighbors on the block were shaken, but most declined to say anything.

Anthony Dellisanti, who lives two doors down, said he saw Seals’ wife raking leaves on the front lawn earlier in the day and one of her kids. Later, he said he saw a number of police officers show up to the house and the family left. They later returned briefly to the house late in the evening, accompanied by officers, and then left once again.

“I thought he was a nice guy, and got along well with him,” said Dellisanti, who would wave to him, but did not know Seals well.

Josephine Gonzalez, lives across the street several houses down, said everyone was mourning him.

“It’s so sad. I didn’t even know it was him when I saw it on the news. And then I was like, ‘Oh my god, that’s the guy on my street,'" recounted Gonzalez. “I’ve seen the older son play soccer in the street. And they have a little baby, it’s so sad. They were happy kids. I saw the mom walk to school with the younger kids or the older son walking the dog. It’s really sad, especially now during the holidays. It’s going to be hard for those kids.”

Joe Vuotolo, another neighbor, called Seals a big family man.

“For Halloween, he would climb up on the house, on the roof and put up these crazy decorations for the kids,” he said. "A really great guy. It’s a shame. It’s a tough thing when you lose somebody. Then when you lose them during the holidays and you’ve got young kids, they’re going to be waiting for Santa Claus.”

Circumstance. Today we tragically lost Joe as he was serving the ppl of Jersey City that he volunteered to serve. I know I speak for all the residents that we are grateful for all he has done for our city. Rest In Peace. — Steven Fulop (@StevenFulop) December 10, 2019

North Arlington Mayor Daniel H. Pronti said the town would be there for the family.

“Joe was not just a resident, he and his family are part of our community,” he said. “It was expected to see the Seals family at our community events. Most of us know each other in our town.”

The mayor said some residents who knew were surprised to learn he was a police officer.

“He kept his work at work and his family in the community. Being in our community, we see each other as family and know one another as our children go to school together,” he said. “We are going to need some time to group together and heal as a community. We will be there for the Seals Family any way they need us.”

Former Jersey City Police Chief Robert Cowan knew Seals well.

“He was a really good street cop. When I was out on the street...I would see him and his partner always out there. They were always working. They were aggressive cops,” he said. “They made the city safer.”

Jersey City Mayor Steve Fulop said Seals was an officer that loved Jersey City.

“Our thoughts and prayers are with Joe’s family during this Christmas season and beyond. We take for granted sometimes the selfless work a police officer does when they wear that uniform. In the end they are people that volunteered to keep everyone else safe regardless of the circumstances,” said Fulop.

Gov. Phil Murphy, who came to Jersey City, called it “an incredibly tough day” for the city and the state of New Jersey.

“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.

Murphy added that the tragedy was also a day that “requires us to stop and think about what it takes to put on a uniform.”

Details of the shooting were still sketchy on Tuesday night, but authorities said the deadly incident began when Seals was shot at around 12:30 p.m. in Bayview Cemetery. A second officer was believed to be shot in the area of Martin Luther King Drive and Bidwell Avenue in Jersey City, before the gunmen who drove away in a stolen rental van engaged police in a protracted shootout.

Officials gave no immediate details on what set off the shooting and how it unfolded.

“He came upon bad guys,” said Kelly. “I don’t know yet how he got there.”

According to news reports, Seals had approached a van linked to a murder in Bayonne over the past weekend and was shot as he came toward the vehicle.

Seals was the 35th Jersey City police officer killed in the line of duty.

Staff reporters Stephen Stirling and Alex Napoliello contributed to this report.

Ted Sherman may be reached at tsherman@njadvancemedia.com. Follow him on Twitter @TedShermanSL. Facebook: @TedSherman.reporter. Find NJ.com on Facebook.

Sophie Nieto-Munoz may be reached at snietomunoz@njadvancemedia.com. Follow her at @snietomunoz. Find NJ.com on Facebook.

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