The suspected shooters, David Anderson and Francine Graham, had five firearms in their possession as well as a simple but working pipe bomb. The pipe bomb and one of the guns was later recovered from a rental van Anderson and Graham used in the attack.
Four of the weapons -- two handguns, a shotgun and a modified AR-15-style rifle -- were found inside the store in the Greenville section where most of the day's violence took place. Anderson was seen in video using the AR-15-type gun and Graham the shotgun. Both were later killed by police, among six people killed Tuesday.
Another handgun, a 22-caliber equipped with a makeshift silencer, was the weapon recovered from the van.
Surveillance video shows the two drive up to the JC Kosher Supermarket on Martin Luther King Drive in the van, park, then exit with guns drawn. They opened fire, killing three people in the store and wounding another man who escaped.
The two are also believed to have shot and killed a Jersey City police officer, Detective Joseph Seals, at a cemetery not far from the grocery store.
In explaining their motive, Grewal said the two specifically targeted the customers in the market, which specialized in goods for the area's Orthodox Jewish community. The two fired on the man, who was dressed in traditional Orthodox Jewish clothing, as he fled the market, ignoring others on the street, Grewal said.
He added that while the two have been linked to a religious movement designated as a hate group, the Black Hebrew Israelites, Anderson and Graham appeared to have "acted alone." No definitive connection between the Black Israelite group and the suspected shooters has been established, but an investigation into social media and other writings was continuing Thursday, Grewal said.
Authorities had been reluctant to suggest a reason why the two went on a violent rampage and still refrained from ascribing a precise motive, but did say Thursday that the evidence strongly suggests the pair "had hatred for the Jewish people as well as hatred towards law enforcement," Grewal said.
Authorities urged residents to promptly report any suspected bias crime by calling 800-277-BIAS (2427).
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