Auburn police Officer Ronald Tarentino was rushed to UMass Memorial Medical Center after getting shot early Sunday during a traffic stop. He later died.

The suspect, Jorge Zambrano, was killed after a four-hour standoff with police in an Oxford neighborhood. There was a shootout between officers and Zambrano in an apartment. A trooper was hit by gunfire but is expected to be OK, the source said.

Tarentino, 42, had transferred from the Leicester Police Department two years ago. He leaves behind a wife and three children.

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State police said the suspect was already gone when they arrived at the intersection where Tarentino was shot. Police say the shooter apparently drove off in a vehicle.

Strangers and other officers lined the roads as a procession with Tarentino's body headed to the Boston Medical Examiner's Office Sunday.