Officer breaks up armed-robbery attempt at Roslindale gas station; suspects on the run, his gun goes off

Boston Police are investigating an armed-robbery attempt at the Alfa gas station at Washington and South streets tonight by three men who apparently fled on foot when a Boston officer arrived on scene.

WBZ reports the officer's gun discharged accidentally as he chased the suspects. The officer was taken to the hospital for observation.

Police are searching backyards between South Street and Forest Hills for three blak men: The gunman,who had a medium to large build and wore a blue jacket with a black ski mask, a blue hoodie, and black pants - and who had a pronounced limp; a man wearing a black jacket with a gray hoodie with long strings hanging from the neck and light bluejeans; and a man wearing a blue North Face jacket with a white or gray hoodie and bluejeans.

Washington Street was shut to traffic on either side of the gas station, although MBTA buses were still allowed through.