BILLERICA, Mass. (AP) – A Tewksbury police officer was shot Wednesday during a struggle with a man accused of robbing a convenience store.

The officer sustained what was described as a “superficial wound” to his leg, said Tewksbury police Chief Al Donovan. He was taken to an area hospital, where he was being treated.

Two other officers also suffered minor injuries during the arrest of Joseph Croteau, who led police on a chase in two towns after allegedly robbing a Mobil station store.

The incident began in Lowell shortly before 11 a.m. when police say Croteau stole a van that someone had left running outside a gas sation.

Croteau then drove to Tewkswbury, police said, and walked into a gas station, jumped over the counter and grabbed money out of the cash register, Donovan said.

At 11:23 a.m. police received a 911 call about a robbery. Croteau drove off in a blue van and was pursued by police from the Tewksbury, then Billerica police departments.

Croteau lost control of the van just over the Billerica town line, crashing into a telephone pole. He fled on foot, but was met by at least two officers.

During a brief struggle, the Tewksbury officer’s gun went off, the bullet striking the officer in the leg. It was unclear if the suspect was going for the gun at the time, or if it was accidentally discharged, police said.