MIT and state police are investigating early Tuesday gunshots heard around 400 Memorial Drive, with no injuries reported and no known direct threats to the campus, according to an afternoon campus advisory to the Massachusetts Institute of Technology community.

It follows threats made Saturday night, when a man said by phone that he planted bombs inside two campus buildings, leading to a response by Cambridge, MIT and state police as well as Cambridge firefighters. No explosives were found, the Cambridge Chronicle reported Tuesday.

MIT Police are seeking information that might be helpful in the investigation at their office at Building W89, 301 Vassar St., or by calling (617) 253-1212 – or anonymously at (617) 258-8477 – or by contacting the State Police by calling 911.

There have been numerous examples this year of early morning gunshots with no victims, but most such incidents have been in The Port neighborhood closer to Central Square.

John Hawkinson contributed to this report.