An imam who was shot Wednesday outside a mosque near New York has died, said a state's attorney who added that the killing did not initially appear to be driven by "bias" or domestic terrorism.

The prosecutor said that the man, Hassan Sharif, was shot multiple times before being taken to hospital where he later died.

"We do not yet know the motivation for this crime (but) the evidence collected thus far does not indicate that this was an act motivated by bias or an act of domestic terrorism," said New Jersey Attorney General Matt Platkin.

"In light of global events, and with a rise in bias that many communities are experiencing across our state — particularly the Muslim community — there are many in New Jersey right now who are feeling a heightened sense of fear," said Platkin.

The state is home to 300,000 Muslim Americans, he said.

Since the outbreak of the Israel-Hamas war, there has been an increase in Islamophobic and anti-Semitic attacks across the United States.

Essex County prosecutor Ted Stephens confirmed Sharif was shot more than once, and that "it does not appear the imam was the victim of a bias crime or that this is related to terrorism."

"We are dedicated to bringing justice for the imam's family," said Stephens, who called it a "dastardly crime."

The United States Transportation Security Administration (TSA) earlier confirmed that Sharif had worked as a security screener at Newark Airport since 2016.

"We are deeply saddened to learn of his passing and send our condolences to his family, friends and colleagues," said Lisa Farbstein, a TSA spokeswoman.

Images published by the New Jersey chapter of the Council on American-Islamic Relations (CAIR) showed police vehicles deployed outside the Masjid Muhammad-Newark mosque, a two-story yellow and green complex.

CAIR was due to hold an event later Wednesday alongside the Newark Interfaith Alliance to demand the shooter hand themselves in to police.