A “significant number” of bullets and shotgun rounds were exchanged between police and an armed robbery suspect during a multitown police chase that ended with the accused robber being fatally wounded in East Bridgewater on Monday, a top prosecutor said Tuesday.
Cape and Islands District Attorney Michael O’Keefe is overseeing the investigation into the use of force that resulted in the death of Jeffrey P. Watts, a 46-year-old Brockton man.
Watts’s relatives could not be reached for comment Tuesday.
According to O’Keefe, Watts entered a CVS store in Brockton armed with a shotgun on Monday afternoon and he demanded “any and all opiates.’’
After he left the store, Watts allegedly started shooting at police with the shotgun and continued to shoot as they pursued him through the heart of Brockton, south into Whitman, and then about 300 yards into East Bridgewater where a final confrontation took place on Thatcher Street.
Area residents said Monday that they heard upward of 30 shots being fired when police and Watts confronted each other there. O’Keefe said one issue under investigation is whether Watts had a second weapon or only the shotgun.
O’Keefe said one goal of his investigation is to determine how many rounds were fired and where along the pursuit the shots were exchanged.
“There were several different locations that gunfire was exchanged,” he said. “There was a significant number of rounds fired during the course of this event. We are doing our best to account for each and every one of them. It’s going to take some time to do that.’’
Brockton and State Police were involved in the chase. East Bridgewater Police Chief John E. Cowan said Tuesday that the incident happened so quickly — at one of the remoter corners of the rural suburb — that it was over by the time he and his officers arrived.
O’Keefe is handling the investigation at the request of Plymouth District Attorney Timothy J. Cruz, who wants to avoid the appearance of bias because one of the state troopers involved in the deadly force case is assigned to his office.
Mayor Linda M. Balzotti of Brockton declined to discuss the incident, which included a Brockton police officer being struck by a projectile in his bulletproof protector during the pursuit. But Balzotti offered her view on the way Brockton police handled the incident.
“I’m very proud of the officers,’’ she said in a telephone interview. “I’m just very grateful that no officer and no bystander was injured.’’
Watts was most recently a Brockton resident.
“I feel badly that a situation transpired like that,’’ she said. “I’m sure there was probably a lot of desperation on his part to do something that is very sad.”John R. Ellement can be reached at ellement@globe. com. Follow him on Twitter @JREbosglobe.