Bomb threats called into multiple Ivy League universities

Brown, Cornell and Columbia University evacuated parts of their campuses on Sunday after receiving bomb threats, just days after another bomb threat was reported at Yale University. It is not clear if the threats are connected, and no suspect has been publicly connected to any of the calls, which were all later deemed to be false threats.

Columbia said it issued "a campus-wide emergency alert" after receiving threats to school buildings. The New York City school warned students to avoid the area while police investigate, but later said the threat was deemed "not credible" and it was safe to return.

Officials at Brown, which is located in Rhode Island, confirmed to CBS News that the school had also received a bomb threat on Sunday, and "evacuated several buildings near the university's college green." A spokesman for the school later issued an all clear, and said buildings that had been evacuated are now reopened.

Cornell, which is located in upstate New York, issued a similar statement, reporting that police "received a call of bombs being placed" in multiple buildings, including the law school. Hours later, the school said "no credible threats were found."

In a statement later Sunday night, the school's vice president of university relations said that just before 2 p.m., 911 dispatchers received an anonymous call from someone who said they were in campus buildings with automatic weapons and had already put explosives in other buildings.

"We are relieved to report that this threat appears to have been a hoax," the statement said. "A cruel hoax; but, thankfully, just a hoax. The University has now resumed its normal operations."

The statement said it was aware of the bomb threats made at other schools, and "will work closely with local, state, and federal investigators pursuing links among these threats of campus violence."

The news comes after multiple bomb threats were called into Yale on Friday, according to CBS New York. Police responded to the scene and gave students the all-clear to return later Friday evening.

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