WATERTOWN, Mass. (AP) - Police say one of two suspects in the shooting of an MIT police officer is dead and a massive manhunt is underway for another, who is tied to the Boston Marathon bombing.
Shortly after the MIT officer was shot Thursday night, police got a report of a carjacking in Cambridge, just outside Boston.
Police say of the at-large suspect, "We believe this to be a terrorist."
The FBI is investigating whether the fatal shooting of a campus police officer at the Massachusetts Institute of Technology and gunfire and explosions in a nearby town are related to the Boston Marathon bombings.
A Massachusetts State Police spokesman said early Friday that one person suspected in the gunfire and explosions has been accounted for and one is at large.
The FBI said it is working with local authorities to determine what happened.
The MIT shooting on the Cambridge campus Thursday night was followed by reports of violence in nearby Watertown, about 10 miles west of Boston.
State police spokesman David Procopio said there is a "strong possibility" the incidents are related.
The MIT officer had been responding to report of a disturbance Thursday night when he was shot multiple times, according to a statement from the Middlesex district attorney's office and Cambridge police. It said there were no other victims.
In Watertown, witnesses reported hearing multiple gunshots and explosions at about 1 a.m. Friday. Dozens of police officers and FBI agents were in the neighborhood and a helicopter circled overhead.
State police spokesman David Procopio said, "The incident in Watertown did involve what we believe to be explosive devices possibly, potentially, being used against the police officers."
Boston cab driver Imran Sais said he was standing on a street corner at a police barricade across from a diner when he heard an explosion.
"I heard a loud boom and then a rapid succession of pop, pop, pop," he said. "It sounded like automatic weapons. And then I heard the second explosion."
He said he could smell something burning and advanced to check it out but area residents at their windows yelled at him, "Hey, it's gunfire! Don't go that way!"
MIT said right after the 10:30 p.m. shooting that police were sweeping the campus in Cambridge and urged people to remain indoors. They urged people urged to stay away from the Stata Building, a mixed-use building with faculty offices, classrooms and a common area.
Hours later, MIT, which has about 11,000 students, said the campus was clear but the shooter was still on the loose.
Sergeant Lucinda Miller was killed in an off-duty accident Monday night. Sergeant Miller had been using a tractor to pull her personal vehicle out of a ditch at her home. Police say the tractor rolled over, killing Miller.
Sgt. Miller joined the police department in 1996 and was promoted to sergeant in June of 2010. She also received an Award of Excellence in 2011.
Her funeral will be Saturday at Kutis Funeral Home in South St. Louis.
Miller is survived by her domestic partner, her daughter and five brothers.