This combination of undated photos shows Tamerlan Tsarnaev, 26, left, and Dzhokhar Tsarnaev, 19. The FBI says the two brothers and 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 a getaway attempt in a long night of violence that left Tamerlan dead and Dzhokhar still at large on Friday, April 19, 2013. The ethnic Chechen brothers lived in Dagestan, which borders the Chechnya region in southern Russia. They lived near Boston and had been in the U.S. for about a decade, one of their uncles reported said. (AP Photo/The Lowell Sun & Robin Young)
A police officer reacts to news of the arrest of one of the bombing suspects on Friday night as people celebrate in the background at Boston Common.
This still frame from video shows Boston Marathon bombing suspect Dzhokhar Tsarnaev visible through an ambulance after he was captured in Watertown, Mass., Friday, April 19, 2013. A 19-year-old college student wanted in the Boston Marathon bombings was taken into custody Friday evening after a manhunt that left the city virtually paralyzed and his older brother and accomplice dead. (AP Photo/Robert Ray)
Police in tactical gear cautiously approach a boat parked in a backyard in Watertown, Mass., where a suspect in the Boston Marathon bombings had taken cover Friday.
BOSTON -- The search for the Boston Marathon bombers ended Friday night to the sound of flash-bang grenades and neighborhood cheers as the second of two brothers was cornered, captured and taken away in an ambulance.
Boston police confirmed about 8:45 p.m. that they had taken Dzhokhar Tsarnaev, 19, into custody, after they discovered him hiding in a boat stored behind a house in nearby Watertown, Mass. A trail of blood tipped off the boat's owner -- and the police -- to Tsarnaev, ultimately leading to an apprehension and climax to a violent week.
"We are so grateful to bring closure and justice to this case," Massachusetts State Police Col. Timothy Alben said at a 9:30 p.m. briefing. "We're exhausted, folks, but we have a victory here tonight."
Rick DesLauriers, special agent in charge of the FBI's Boston field office, added that "it seems like many months since Monday," when the horrific marathon explosions occurred. He stressed that this was a "truly intense investigation" involving myriad officers with the multi-agency Joint Terrorism Task Force.
Specially trained operators with the FBI's elite Hostage Rescue Team made the capture, following a standoff and exchange of gunfire.
Tsarnaev was taken to a hospital where doctors declared he was in serious condition. The U.S. attorney for Massachusetts, Carmen Ortiz, said Friday night that no decision had yet been made about whether to seek the death penalty.
Tsarnaev's brother, Tamerlan Tsarnaev, 26, had died after a shootout with law enforcement officers early Friday morning, but Dzhokhar Tsarnaev escaped, setting off an extraordinary manhunt that captivated and stilled one of the nation's most vibrant cities.
The FBI confirmed that two years ago it interviewed Tamerlan Tsarnaev at the request of a foreign government. The agency did not identify the government involved but concluded at the time that Tsarnaev was not a threat.
On Friday, following a frantic search that essentially shut down Boston for much of the day, Franklin Street residents in Watertown heard a flurry of gunshots around 7 p.m. Law enforcement and emergency vehicles arrived, sirens screaming, at the scene, setting up a perimeter that was reinforced by the minute.
About 8 p.m., residents heard a number of flash-bang grenades, commonly used to disorient suspects; some time later, law enforcement officers could be heard urging Dzhokhar Tsarnaev to give up.
"We always want to take all suspects alive," Boston Police Commissioner Edward Davis said Friday night.
When it became clear that Tsarnaev had surrendered, neighbors burst into cheers and applause. Later in the evening, public celebrations spread to other parts of the city. Downtown Boston streets were crowded with cheering people.
"Thank you, thank you, thank you," Boston Mayor Tom Menino said Friday night.
President Barack Obama also praised the efforts of everyone involved and directed federal law enforcement and intelligence agencies to continue the investigation into what links -- if any -- the suspects may have had with terrorist groups.
"Boston police and state police and local police across the commonwealth of Massachusetts responded with bravery over five long days," he said. "We are extremely grateful. … We owe a debt of gratitude."
After shutdown lifted
The climax came shortly after Massachusetts Gov. Deval Patrick gave a green light for the city's mass transit system to reopen, returning at least a touch of normalcy to a metropolis that's been stricken since the Monday bombings and that went into full-scale lockdown Friday. Boston officials had halted the city's mass transit system and urged residents to "shelter in place" before finally giving workers the go-ahead to leave for home in the early afternoon. While mass transit resumed about 6 p.m., the Boston Bruins and the Red Sox canceled their night games.
Even the downtown streets in Boston were deserted, with few people out and most stores closed. An Au Bon Pain restaurant that posted it was closing at 4 p.m. was quickly mobbed, as if a hurricane were approaching. Patrons grabbed bottles of water and cleaned out the case of ready-made sandwiches.
Officials also locked down and later evacuated the University of Massachusetts-Dartmouth, a campus about 60 miles from Boston, where the younger Tsarnaev is a student. By midafternoon, National Guard helicopters were landing at the campus and off-loading what appeared to be SWAT teams.
Officials revealed that a resident alerted the Watertown Police Department to the potential hiding site late Friday. The neighborhood had been locked down all day, but law enforcement officials advised residents after 6 p.m. that it was safe to go outside. One Franklin Street resident went to check on his boat.
"He happened to notice that the boat didn't look right, so he looked inside. That's where he saw the blood and the body," Franklin Street resident George Pizzuto told ABC.
Investigators identified the two brothers as suspects in the Monday bombings, which happened around 2:50 p.m. near the finish line of the Boston Marathon. The blasts killed three people and wounded nearly 200. Physicians have performed multiple amputations on victims, whose ages range from 2 to 78.
Motive a mystery
The unanswered questions include any idea of motive or explanation for how the two brothers came to be possible murderers.
"Somebody radicalized them," the brothers' uncle, Ruslan Tsarni, told reporters outside his suburban Maryland home late Friday morning.
In one hint of potential radical interests, a profile published under Dzhokhar Tsarnaev's name on a Russian-language social media site resembling Facebook had links to news videos about terrorist attacks on the subways in Moscow and in the Belarus capital of Minsk.
The uncle, Ruslan Tsarni, told reporters that the brothers were ethnic Chechens, though they were not born in Chechnya. The younger brother was born in Kyrgyzstan, Tsarni said. The suspects' aunt, Maret Tsarnaev, said on Canadian television that the father worked as a lawyer and in an "enforcement" agency in his home country, which she said eventually put him at risk.
The aunt said she was living in the United States in April 2002 when Dzhokhar arrived along with his mother and father, while the other brother and two sisters remained with relatives in Kazakhstan. The family petitioned for refugee status; the father and mother are now living in the capital city of the Russian republic of Dagestan, where the father, Anzor, told television reporters Friday that he suspected his sons may have been set up as fall guys for what he denounced as a heinous attack in Boston.
"I honestly can't imagine who could do this," the father told a Dagestan TV station. "Whoever did this is a bastard."
Chechen President Ramzan Kadyrov, in a Russian-language Internet posting translated by McClatchy, vigorously distanced his war-torn country from the two suspects.
"It would be useless to try to make any connection between Chechnya and these Tsarnaevs, if they are indeed guilty," the president wrote. "They grew up in the United States; their attitudes and beliefs were formed there. The roots of this evil must be sought in America."
Christopher Swift, adjunct professor of national security studies at Georgetown University, further pointed out that there are big cultural and language differences between Arab and Chechen Muslims.
"They are totally different cultures," Swift said. "It's like Greek people going to Ireland. … There's a big difference between Irish Catholicism and Greek Orthodox Christianity as practiced in Greece."
The older brother, Tamerlan, was studying at Bunker Hill Community College and had been a boxer. He was married.
The younger brother, Dzhokhar, attained his U.S. citizenship on Sept. 11, 2012. Known by friends and family members as Jahar, he was a student and wrestler at the Dartmouth satellite campus of the state university.