The U.S. attorney in New Jersey and the head of the local FBI said today that the bomb found in the van of alleged domestic terrorists Francine Graham and David Anderson could have killed or maimed people up to five football fields away, NBC NEWS reports.

They also said there was enough material in the van to make a second bomb.

Four innocent people, including a veteran Jersey City police detective and father of five, died in the hail of prolonged gunfire. Most of the victims were found inside the JC Koshoper Supermarket on Martin Luther King Boulevard during what officials have described as a hate-fueled terror spree on Dec. 10.

The officer who died, Det. Joseph Seals, was killed at a cemetery, where authorities said he had gone to meet with a man to talk about the return of a vehicle impounded by police. Details will never be definitive, authorities said, but investigators believe Seals approached the suspects’ van because cops were looking for it in connection with the murder of a livery driver the prior weekend. Cops are still looking into a possible connection between the driver’s death and the terror that was unleashed in Jersey City on Dec. 10.

Seals’ death first brought law enforcement near the scene of what would become a horrific bloodbath, leaving schools with bullet-riddled windows and the neighborhood locked down.

Authorities could not detail what that plan would have been, other than to say that Graham and Anderson had done research on a Jewish community center in Bayonne. They did confirm earlier preliminary suspicions that the shootout was a bias crime against Jews and against the law enforcement community. The shooters were found dead when the gunfire ended.

Authorities do not believe a Yeshiva next door to the kosher supermarket was targeted, but said they had cased the grocery store multiple times, including the morning of the attack. Carpenito also confirmed a News 4 report that several days before the shooting, a Jewish man driving near Newark Airport had been shot at; ballistics show two of the shots that hit the man’s car came from one of Anderson and Graham’s guns. The livery driver who died the weekend before the attack was shot with the same weapon that fired on the vehicle near the airport, authorities said. Read more at NBC NEWS.