BOSTON -- Police say after having searched the campus of Massachusetts Institute of Technology that reports of a gunman on the campus were unfounded.

Shortly after 9 a.m. today, the campus was placed on lockdown after reports that a man carrying a long rifle and wearing body armor was spotted in a campus building.

MIT said in a statement Saturday that several law enforcement agencies responded.

About 10:45 a.m., MIT posted a notice on a school website saying that Cambridge Police had issued an all clear and campus operations were returning to normal.