CAMBRIDGE, Mass. (AP) — A false report of a gunman at the Massachusetts Institute of Technology that briefly caused a campus-wide lockdown Saturday stemmed from an electronic message sent to police, authorities said.

Officers searched for a man reported to be carrying a long rifle and wearing body armor but found nothing unusual, Cambridge police said. The report — that alleged the gunman was barricaded inside a building on campus — turned out to be a hoax, and there was no threat to public safety, state police spokesman David Procopio said.

Cambridge police received the tip in an electronic message around 7:30 a.m., but witnesses on the scene eventually contradicted it, spokesman Dan Riviello said. Neither police nor MIT specified how the tip was received, though the police department's website says anonymous tips may be made via text message or email, in addition to a telephone hotline.