PRINCETON — An hours-long standoff with a gunman inside a Panera near Princeton University ended late Tuesday afternoon when police shot and killed him.

The armed standoff started around 10:30 a.m. at the restaurant on Nassau Street.

Customers and employees fled the building before police arrived and attempted to negotiated with him. The man was killed just before 3 p.m., according to the state Attorney General's Office, which routinely investigates police-involved shootings.

Police block off Nassau Street in Princeton. (Janos Hovac)

The man was pronounced dead on scene. Authorities did not release his name late Tuesday because they were trying to first notify his family.

There were no hostages.

A passerby, Susanna Troy, told New Jersey 101.5 she was walking near the eatery when she noticed a parking enforcement officer and a female police officer crouched with her gun outside Panera.

Police closed busy Nassau Street and heavily armed officers from the State Police, FBI, the university, borough and neighboring West Windsor descended on the scene.

Princeton public school students were ordered to shelter in place at the district's seven schools.

Police block off Nassau Street in Princeton. (Janos Hovac)

Princeton University said Henry House and Scheied-Caldwell were evacuated as a precaution. The university recalled an automated alert officials had accidentally sent to students and employees stating that shots had been fired earlier in the standoff.

To contact an editor about this story, email New Jersey 101.5 Deputy Digital Editor Sergio Bichao at sergio.bichao@townsquaremedia.com

Sign up for the NJ1015.com Newsletter

Get the best of NJ1015.com delivered to your inbox every day.