SOMERVILLE, Mass. (AP) — Massachusetts state police say a suspect has been arrested after someone fired a weapon at officers responding to a bank robbery in Somerville.

State police tweeted Wednesday morning that the unidentified suspect was in custody, but they say it's not clear whether the person was the shooter. They said a search continued for others who may have been involved.

Somerville residents were being urged to stay indoors. State police said the MBTA's Davis Square station in Somerville was closed as a precaution.

There were no immediate reports of injuries. Authorities say multiple state police units were sent to the area just north of Boston.