Residents warned not to open doors
12:40 p.m.: Police, federal agents and military personnel are going door-to-door searching for the teenage bombing suspect who has eluded capture since being located late Thursday. Massachusetts state officials said residents should keep doors locked and not open their door unless it's a uniformed police officer knocking. New leads have been developed and the search and sweep of the area could continue through the weekend. The suspect is assumed to armed with explosives. AMTRAK suspends commuter line service in the Boston, Washington and New York corridor.
Uncle pleads with suspect: 'Turn yourself in; seek forgiveness'
Noon: The uncle of the bombing suspects, Ruslan Tsarni, made a statement to reporters outside his home at about 11:30 a.m. He offered his condolences to the victims of the bombing, expressing his shock and sorrow that his family would be linked to such a tragedy. He hadn't been in contact with his brother or nephews since 2005. "I just wanted my family to be away from them," he said. "Of course we're ashamed. They're children of my brother." To his nephew that remains at large, he said: "Turn yourself in, and ask for forgiveness.
Feds waiting out suspect
11:20 a.m.: Federal agents, police and military officials hope to apprehend the Boston bomb suspects alive as they continue surrounding an area inside a Cambridge neighborhood in what is likely the largest manhunt in U.S. history. A news conference is scheduled to begin shortly.
Be on the lookout
11 a.m.: Federal agents have cordoned off a Cambridge neighborhood and bomb squads are sweeping the area for explosives, while authorities continue searching for at least two, or more suspects in the Boston Marathon bombing. The New York Times is reporting that police in Connecticut and Massachusetts were notified to be on the lookout for a Gray Honda CR-V with Massachusetts plates that they had been looking for in Cambridge, Mass.
Military, federal agents and police converge
9:45 a.m. : A third suspect is being pursued by federal authorities, who stopped a train in Conneticut and surrounded the commuter rail line this morning. Military bomb squads are sweeping a five-block area where a second bomb suspect was believed holed up. A third suspect was killed overnight in a shootout with police after a convenience store robbery. The city and suburbs of Boston are on lockdown.
9 a.m.: Reports are surfacing that federal agents and police might have have the surviving bomb suspect pinned down but fear he might be armed with more explosive. Check back here for updates. Bomb squads have been sent into buildings in area where the supect was believed holed up.
Shelter in place
8:45 a.m.: (AP) Boston's police commissioner says all of Boston must stay in their homes as the search for the surviving suspect in the marathon bombings continues. Commissioner Ed Davis made the announcement Friday morning, after a long night of violence that left the other suspect dead.
The suspects were identified to The Associated Press as coming from the Russian region near Chechnya, which has been plagued by an Islamic insurgency stemming from separatist wars.
A law enforcement intelligence bulletin obtained by the AP identified the surviving suspect as Dzhokhar A. Tsarnaev (JOE-khar Tsahr-NEYE-ev), 19, of Cambridge, Mass.
The two men are suspected of killing a Massachusetts Institute of Technology police officer on campus in Cambridge late Thursday, then stealing a car at gunpoint and later releasing its driver unharmed.
The suspects' clashes with police began only a few hours after the FBI released photos and videos of the two young men, who were seen carrying backpacks as they mingled among revelers at Monday's Boston Marathon. The bombings on Monday killed three people and wounded more than 180 others, and authorities revealed the images to enlist the public's help finding the suspects.
Bomb suspect located
8:30 a.m.: The city is on lockdown and reports indicate police and federal agents have pinpointed the location of the surviving bomb suspect. His older brother was killed in a shootout with police. It's not clear whether the suspect is holed up alone or with others. Residents in the area have been ordered to "shelter in place," with public transportation shut down across the region.
8:00 a.m.: (AP) Manhunt continues.
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Police kill one suspect
6:47 a.m. (AP) Two suspects in the Boston Marathon bombing killed an MIT police officer, injured a transit officer in a firefight and threw explosive devices at police during their getaway attempt in a long night of violence that left one of them dead and another still at large Friday, authorities said as the manhunt intensified for a young man described as a dangerous terrorist.
In Boston, still on edge over the attack on the marathon, and its western suburbs, authorities suspended mass transit and urged people to stay indoors as they searched for a man seen wearing a white baseball cap on surveillance footage from Monday's deadly bombing at the marathon finish line.
"We believe this man to be a terrorist," said Boston Police Commissioner Ed Davis, who urged nearby residents to stay in their homes unless police are present. "We believe this to be a man who's come here to kill people."
Authorities urged residents in Watertown, Newton, Arlington, Waltham, Belmont, Cambridge and the Allston-Brighton neighborhoods of Boston to stay indoors. All mass transit was shut down, and businesses were asked not to open Friday. At least a quarter of a million people live in those suburbs. People waiting at bus and subway stops were told to go home.
All modes of public transportation were shut down, including buses, subways, trolleys, commuter rail and boats, said Joe Pesaturo, spokesman for the Massachusetts Bay Transportation Authority.
The clashes with police began only a few hours after the FBI released photos and videos of the two young men, who were seen carrying backpacks as they mingled among marathon revelers. The bombings on Monday killed three people and wounded more than 180 others, and authorities revealed the images to enlist the public's help finding the suspects.
The images released by the FBI depict two young men, each wearing a baseball cap, walking one behind the other near the finish line. Richard DesLauriers, FBI agent in charge in Boston, said the suspect in the white hat was seen setting down a bag at the site of the second of two deadly explosions.
Authorities said surveillance tape recorded later Thursday showed the suspect known for the white hat during a robbery of a convenience store in Cambridge, near the campus of MIT, where a university police officer was killed while responding to a report of a disturbance, said State Police Col Timothy Alben. The officer died of multiple gunshot wounds.
From there, authorities say, two men carjacked a man in a Mercedes-Benz, keeping him with them in the car for half an hour before releasing him at a gas station in Cambridge. The man was not injured.
The search for the vehicle led to a chase that ended in Watertown, where authorities said the suspects threw explosive devices from the car and exchanged gunfire with police. A transit police officer was seriously injured during the chase, authorities said.
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.
Watertown resident Christine Yajko said she was awakened at about 1:30 a.m. by a loud noise, began to walk to her kitchen and heard gunfire.
"I heard the explosion, so I stepped back from that area, then I went back out and heard a second one," she said. "It was very loud. It shook the house a little."
She said a police officer later knocked on her door and told her there was an undetonated improvised explosive device in the street and warned her to stay away from the windows.
"It was on the street, right near our kitchen window," she said.
Yajko said she never saw the suspect who was on the loose and didn't realize the violence was related to the marathon bombings until she turned on the TV and began watching what was happening outside her side door.
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 Saif 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!"
Doctors at a Boston hospital where a suspect in the marathon bombings was taken and later died are saying they treated a man with a possible blast injury and multiple gunshot wounds.
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 Center, a mixed-use building with faculty offices, classrooms and a common area.
The suspects' images were released hours after President Barack Obama and first lady Michelle Obama attended an interfaith service in Boston to remember the dead and the wounded.
At the Cathedral of the Holy Cross, Obama saluted the resolve of the people of Boston and mocked the bombers as "these small, stunted individuals who would destroy instead of build and think somehow that makes them important."
"We will find you," he warned.
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MIT police officer shot and killed
April 18, 2013, 10:30 p.m.: (AP) Police have converged on a neighborhood outside Boston where there were reports of explosives being detonated and police are telling reporters to turn off their cell phones.
Dozens of officers and National Guard members are in Watertown, where television outlets report that gunfire and explosions have been heard. A helicopter is circling overhead.
Authorities early Friday were calling for somebody to get on the ground and put their hands up and a loud thud was heard after someone shouted "fire in the hole."
Reporters are being told to move away from the scene. A police officer told a reporter: "If you want to live, turn off your cell phone."
Earlier Thursday night a campus police officer was shot and killed at MIT and authorities were searching for the person responsible.