A man's leg was grazed by a bullet around 10:20 p.m. on Thursday at the busway at Ashmont station.
He was taken to Carney Hospital. The station was briefly shut as Transit and Boston police investigated. Police were looking for two black men and one white man.
About 30 minutes later, the TJ convenience store at 80 Welles Ave. was held up at gunpoint by a man who ordered workers to the ground.
The suspect is described as a black man, about 35 and 6'2" or 6'3." He wore a mask, a gray hoodie with a large Adidas logo and black and white sneakers.