A man already awaiting trial on drug charges in Woburn was arrested at the Andrew Square Red Line stop after he allegedly punched another man in the face and then used a knife to slash his face and arm Friday evening, Transit Police report.
According to police, Donald Ahlgren, 37, of Watertown, went up to the other man around 6:50 p.m. and "without provocation closed-fist struck the victim in the face and then produced a knife and proceeded to assault the victim in the face and arm with the knife."
Police say officers found Ahlgren standing near the fare gates, along with the knife he used. As he was taken to Transit Police headquarters on Southampton Street for booking, his victim was taken to a local hospital for treatment of injuries not considered life threatening.
On Sept. 29, Ahlgren was arrested in Watertown on three warrants out of Woburn District Court, two related to drug possession.