Former Arizona State University assistant professor charged in Liberty Bell threat

Police have charged a former Arizona State University assistant professor with making terroristic threats for allegedly claiming to have explosives Saturday morning as he entered the Liberty Bell Center.

Carlos J. Balsas, 41, of Tempe, Ariz., entered the center shortly after 10 a.m. and, like all visitors, encountered a security check. Police said a security officer began searching Balsas's backpack when Balsas said, "I have explosives in there." He then left.

When National Park Service rangers stopped Balsas in the 700 block of Market Street, he was uncooperative and struggled briefly before being handcuffed, police said.

Authorities closed Market Street to vehicles and pedestrians between Seventh and Eighth Streets around 10:45 a.m. Bomb squad officers found no evidence of explosives, and the street was reopened at 11:45 a.m.

Balsas was also charged with bomb threats, possessing an instrument of crime, reckless endangerment, and related offenses. The investigation was conducted jointly by Philadelphia police and the FBI.

The U.S. Attorney's Office was expected to take over the investigation Monday.