A social media page of one of the two suspects, who targeted a kosher grocery store in New Jersey where three people were killed, had anti-police and anti-Jewish writings posted on it, NBC News is reporting.

Law enforcement sources identified the suspects as David Anderson and Francine Graham, according to NBC News. Authorities have yet to officially identify the attackers.

Anderson was said to be a one-time follower of the Black Hebrew Israelite movement, NBC News reported. Anti-police and anti-Jewish writings were discovered on his social media page, the network news said. Investigators were trying to determine if he had posted the writings.

Investigators also found a manifesto-style note inside the suspects’ van, The New York Times is reporting.

Three people were found dead inside the Jersey City store after the Tuesday standoff. Anderson and Graham were also discovered dead inside.

Jersey City police Det. Joseph Seals also was killed on Tuesday. Earlier, while investigating a murder, he had approached two suspects and one of them shot and killed him, sources told NBC News. Officials have declined to detail how his death was connected to the grocery store standoff.

Meanwhile security footage showed the two suspects in a U-Haul van, stopping outside the store with long guns.

"There were multiple other people on the streets," Public Safety Director James Shea said. "There were many other targets available to them that they bypassed to attack that place. So it was, clearly, that was their target, and they intended to harm people inside there."