One month later, there are still many lingering questions -- including why Detective Joseph Seals was in Bay View Cemetery when was killed and why the suspects targeted the grocery store. Investigators did their best to answer what they could.
First, in addition to the murder of livery driver Michael Rumberger in Bayonne on December 7, 47-year-old David Anderson and 50-year-old Francine Graham are also suspects in a shooting on December 3 near Newark Airport in whicch the windows were shot out of a car driven by a Hasidic man.
Authorities say the victim in that case did not realize he was targeted until after the Jersey City shooting, and one of the suspect's cell phones was tracked to that location on the day of that shooting.
"Up until the attack, there wasn't anything that would have put either of them on anybody's radar," said Gregory Ehrie, special agent in charge of the FBI's Newark division.
Officials say there was evidence that the suspects had been planning the attack for months and that they checked out the JC Kosher Market on Martin Luther King Drive on at least two occasions and entered the store during one of them, even driving by the business twice on the day of the shootings.
They also searched other Jewish locations, however, so it is unclear why they settled upon that as their target.
It is also clear their motivation was anti-Semitic and anti-police views, authorities said, as writings showed they clearly hated both.
At the scene, a note found on Anderson contained a reference to a 1990s documentary, "The FBI's War on Black America," which explored the FBI's targeting of individuals involved in the civil rights movement in the 1960s, U.S. Attorney Craig Carpenito said. He added that a timestamp written on the note corresponded to a segment in the documentary where an interviewee advocates killing "fascist pig cops."
Anderson's social media posts included a reference to Jews as "imposters who inhabited synagogues of Satan," Carpenito said.
"This was a senseless and cowardly act," Carpenito said.
Finally, they say Detective Joseph Seals was at the cemetery to meet an informant when he recognized the suspects' stolen U-Haul from the Bayonne shooting and went to investigate.
In addition to Seals' murder, the suspects also killed 24-year-old Moshe Deutsch, 49-year-old Douglas Miguel Rodriguez, and 31-year-old Mindy Ferencz inside the grocery store.
It appears Rodriguez died as he was holding the back door open to allow another wounded customer to escape.
Now, one month later, Ferencz's husband says he forgives.
"Life should go on and people should start loving each other instead of hating each other, he said. "I'm gonna collect myself with the kids, life is gonna move on."
Authorities said Rumberger was killed with the same weapon used to shoot the vehicle near Newark Airport days earlier and that his blood was found on a Bible in the U-Haul vehicle, which also contained a pipe bomb.
The homemade explosive was powerful enough to send shrapnel over five football fields, and the suspects reportedly had enough bomb making material to make another device.
"They had a viable explosive device, which could have led to mass casualties," U.S. Attorney Craig Carpenito said. "It's impossible now to get inside of their heads because they're no longer with us, and there are no living co-conspirators that we know of, but given the arsenal they had, the weapons they had the ammunition they had, the explosive, it's possible they were looking to target a larger community."
They were apparently looking at another Jewish community center in Bayonne as a possible target, and it is now believed their encounter with Det. Seals slowed their progress and may have saved lives.
They don't have any evidence to suggest the Yeshiva above the Kosher market was the target, a claim previously made by Mayor Steven Fulop, since officials said it was clear they had the sights set on the market.
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