Earlier, a bullet-riddled SUV was recovered in the city’s Watertown section and the FBI searched a home in Cambridge where the brothers were believed to have lived. A woman was taken from inside the building, but it was not known if she had any connection to the suspects.
Police believe the two suspects from Monday’s terror attack are Chechen brothers, Muslims possibly from Dagestan, a province in Russia that borders Chechnya. The man on the loose was identified as Dzhokhar A. Tsarnaev, 19, of Cambridge, Mass. They are believed to have been here for “several years,” sources said, and potentially up to a decade.
“We have several other new leads that have just developed with the past few minutes,” said Massachusetts State Police Police Superintendent Timothy Alben, speaking at a news conference early Friday afternoon. He said police had covered “60 to 70 percent” of the perimeter, inside which they believe Tsarnaev is hiding.
Police believe Tsarnaev could be armed and consider him extremely dangerous. He and his brother — in a vehicle they carjacked from a man who later escaped — led police on a chase through city streets after robbing a 7-11 in Cambridge and killing a Massachusetts Institute of Technology police officer, according to authorities.
The suspects threw explosives from the car and exchanged gunfire with police who were in pursuit as it headed into Watertown, according to the district attorney’s news release. Tamerlan Tsarnaev, 26, was shot several times in the gunfight and pronounced dead late Thursday at an area hospital. But his younger brother escaped, and continued to elude authorities, who were going door-to-door all morning in Watertown.
“Suspect No. 1 is dead, Suspect 2 is on the run,” Massachusetts Gov. Deval Patrick said at a Friday morning press conference. “There is a massive manhunt underway.”
Police also found a car believed to be registered to Tamerlan Tsarnaev in Boston, after earlier issuing a lookout bulletin to Connecticut State police. The Black Hawk choppers were flying above Watertown “to provide extra eyes,” sources told The Boston Globe.
During the pursuit, a MBTA transit police officer was seriously injured and transported to the hospital, according to a news release. He was identified as Richard H. Donahue Jr., 33, and was being treated at Mt. Auburn Hospital.
Witnesses told The Associated Press they heard 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 told the news agency: “The incident in Watertown did involve what we believe to be explosive devices possibly, potentially, being used against the police officers.”
Doctors at Beth Israel Deaconess Medical Center in Boston where a suspect in the marathon bombings was taken and later died said they treated a man with a possible blast injury and multiple gunshot wounds. They wouldn’t say if the patient they treated, who came in with police, was the suspect in the black hat from marathon surveillance footage.
Schools are closed, train and bus service is suspended and police were telling residents of neighborhoods including Cambridge, Waltham, Watertown, Newton, Arlington and Belmont to stay indoors.
The suspects apparently surfaced just hours after the FBI released their imaged late Thursday afternoon, going on a bloody rampage that claimed the life of MIT Police Officer Sean Collier, 26. He was found shot to death in his squad car at 10:20 p.m. Thursday. It was not clear if he was killed before or after the convenience store was robbed, at about 10 p.m.
“The MIT Police serve all of us at the Institute with great dignity, honor and dedication,” Israel Ruiz, MIT’s executive vice president and treasurer, said in a statement. “Everyone here — those who knew Officer Collier, and those who did not — are devastated by the events that transpired on our campus last night. We will never forget the seriousness with which he took his role protecting MIT and those of us who consider it home.”
Earlier Friday, Cambridge police and the Middlesex District Attorney’s office said the MIT officer was responding to a report of a disturbance when he was shot multiple times late Thursday. He later died at a hospital. His name was not immediately released.
Procopio said the shooting took place about 10:30 p.m. outside an MIT building. The area was cordoned off and surrounded by responding law enforcement agencies, according to a posting on the university’s website.
The shooting came little more than three days after the twin bombings on the Boston Marathon that killed three people, wounded more than 180 others and led to an increase in security across the city.
Fox News’ Jennifer Griffin, Jana Winter, Mike Tobin, Mike Levine, Griff Jenkins and The Associated Press contributed to this report