This is a breaking news story. Check back for updates.
UPDATE 12:24 p.m. EST: The Boston Globe, citing Massachusetts State Police, tweets that there was no gunman on the UMass-Boston campus.
"There is no threat. False report. Scene is clear," state police told the Globe.
A building on the campus of UMass-Boston was evacuated Monday afternoon amid reports of a person with a firearm on the campus.
UMass-Boston sent out the following tweet about the incident from its Twitter account at 11:55 a.m. EST:
UMass Boston Alert: Evacuate McCormack Building. Possible person with a firearm. Avoid area. Officials are on scene.
â€” UMass Boston (@UMassBoston) December 16, 2013