A hourslong armed standoff at the Panera Bread shop near Princeton University came to an end after police shot and killed the suspect, according to the New Jersey Attorney General’s Office.

Officials say that a man armed with a gun entered the shop on Nassau Street around 10 a.m. Tuesday. Witnesses tell News 12 New Jersey that the man told customers to leave the store. He then allegedly refused to come out when police arrived.

Authorities had shut down Princeton's downtown area, and two Princeton University campus buildings were evacuated as a precaution. Armed officers were staged outside the restaurant with their weapons drawn during negotiations.

Officials say that negotiations were not successful and that the suspect was shot and killed by police shortly before 3 p.m. No other injuries were reported.

It was not clear what sparked the standoff. The restaurant is located across the street from the university.