BOSTON --A timeline of key events in the search for the suspects wanted for the Boston Marathon bombings.
- Friday - April 19 [7:05 p.m. PT]: President Barack Obama addressed the national from the White House briefing room after the capture of Boston Marathon bombing suspect Dzhokhar Tsarnaev. The president promised to seek answers on motive, methods and whether bombers had help. He said the nation owes a debt of gratitude to law enforcement officials and the people of Boston for their help in the search for the men.
"Tonight we close an important chapter in this tragedy," President Obama said.
- Friday - April 19 [6:35 p.m. PT]: Officials hold a news conference to discuss the arrest of Boston Marathon bombing suspect Dzhokhar Tsarnaev. Police say Dzhokhar fired shots from the boat he was hiding on, and confirmed he is hospitalized in serious condition.
Police say an infrared camera mounted on a helicopter helped confirm the suspect's hiding place in a boat owned by a Watertown, Mass., resident. "We are so grateful to be here right now. We are so grateful to bring justice and closure to this case," says Mass. Police Col. Timothy Alben.
"Everyone worked so well and so hard together to bring us to tonight's conclusion," said Mass. Gov. Deval Patrick. "It's a night when I think we're all going to rest easy."
- Friday - April 19 [6:20 p.m. PT]: Federal law enforcement officials will invoke the public safety exception to the Miranda law and not offer the suspect the right to remain silent during his interrogation, ABC News has learned. The exception is invoked in instances in which the public is at risk of a clear danger. The federal government's high value detainee interrogation group will be responsible for questioning Dzhokhar Tsarnaev.
- Friday - April 19 [6:15 p.m. PT]: Federal sources tell ABC News that the suspect, Dzhokhar Tsarnaev, was seriously injured by a "flash bang" grenade and is bleeding badly. The precise extent of his injuries is unknown at this time.
- Friday - April 19 [6:10 p.m. PT]: Contacted by ABC News, the father of captured bombing suspect Dzhokhar Tsarnaev advises his son to "tell the police everything. Everything. Just be honest."
- Friday - April 19 [5:55 p.m. PT]: The Boston PD Tweets, "CAPTURED!!! The hunt is over. The search is done. The terror is over. And justice has won."
- Friday - April 19 [5:45 p.m. PT]: Boston bombing suspect Dzhokhar Tsarnaev is taken into custody alive, Boston PD confirms. Officers continue sweeping the area. Spontaneous applause breaks out among police and onlookers surrounding the scene and residents take to the streets to cheer police.
- Friday - April 19 [5:05 p.m. PT]: A Watertown, Mass., homeowner spotted blood and body in a covered boat kept in his yard, neighbor and eyewitness George Pizzuto tells ABC News. The homeowner discovered the person, after removing the boat's cover. He then called police.
- Friday - April 19 [4:55 p.m. PT]: New Bedford police confirm to ABC News that three "college age" individuals were taken into custody for questioning by the FBI late this afternoon in connection with the manhunt for bombing suspect Dzhokhar Tsarnaev.
- Friday - April 19 [4:15 p.m. PT]: Three SWAT units are seen arriving on scene of apparent gunfire in Watertown, Mass. Shortly after, more loud bangs were heard.
- Friday - April 19 [4:15 p.m. PT]: Three SWAT units are seen arriving on scene of apparent gunfire in Watertown, Mass.
- Friday - April 19 [4 p.m. PT]: Gunfire is heard in Watertown, Mass., where the search continued for Boston Marathon bombing suspect Dzhokhar Tsarnaev. Heavy police presence seen in the area of Franklin Street. Residents are asked to remove in their homes.
- Friday - April 19 [3:40 p.m. PT]: Law enforcement sources tell ABC News that the FBI interviewed Tamerlin Tsarnaev, 26, two years ago on behalf of a foreign government. They found nothing suspicious and closed the file.
- Friday - April 19 [3:35 p.m. PT]: A student who attends UMass Dartmouth with Dzhokhar Tsarnaev, tells ABC News the suspect was on campus on Tuesday, the day after bombing and acted nonchalant.
- Friday - April 19 [3:10 p.m. PT]: Massachusetts Gov. Patrick Deval announces that mass transit is resuming and the "stay indoors" order is being lifted even though one suspect remains on the lam. State police say that suspect, Dzhokhar Tsarnaev, fled on foot and there is indication he has a vehicle. They believe he is still in the state because of his ties to the area.
- Friday - April 19 [2:55 p.m. PT]: Police say more than 200 spent rounds as well as homemade bombs were found in Watertown, Mass., the site of a shootout between police and the suspects Thursday night and where Tamerlan Tsarnaev, 26, was killed.
- Friday - April 19 [2 p.m. PT]: Law enforcement officials tell ABC News that suspect Dzhokhar Tsarnaev ran over his own wounded brother, Tamerlan Tsarnaev, as he fled police following a shootout Thursday night.
- Friday - April 19 [1:45 p.m. PT]: Additional explosive devices were recovered during the course of Friday's investigation, law enforcement officials tell ABC News.
- Friday - April 19 [1 p.m. PT]: State Department officials confirm that bombing suspect Dzhokhar Tsarnaev came to the United States in 2002 with his father and his mother on a regular visa and then applied for refugee status. He and his parents became U.S. citizens on September 11, 2012. Tamerlan Tsarnaev arrived in the U.S. in 2003, but never became a citizen.
- Friday - April 19 [1 p.m. PT]: U.S. officials confirms that Dzhokhar Tsarnaev came to the United States in 2002 with his father and his mother on a regular visa and then applied for refugee status. Tamerlan Tsarnaev came to the United States the following year. Dzhokhar, his father and his mother became U.S. citizens on September 11, 2012.
- Friday - April 19 [12:05 p.m. PT]: FBI confirms they are no longer looking for green Honda Civic; it has been located and searched.
- Friday - April 19 [12 p.m. PT]: The Boston Bruins and Red Sox canceled their games for the evening, and the Big Apple Circus canceled a scheduled performance, according to the Boston Police.
- Friday - April 19 [11:25 a.m. PT]: The FBI removed a computer from the New Jersey home of the sister of the Boston Marathon bombing suspects. Police said she was cooperating with the investigation and was "heartbroken, surprised and upset," though she told reporters she wasn't sure the accusations against her brothers were true. The woman, identified by local police as Ailina Tsarnaeva, told federal agents she had not been in contact with her brothers for years, according to Police Director Michael Indri.
- Friday - April 19 [11 a.m. PT]: A new vehicle search is announced. Boston authorities say the Dzhokhar Tsarnaev may be traveling in a four-door green Honda Civic with Massachusetts license plate 116-GC7.
- Friday - April 19 [10:40 a.m. PT]: A spokeswoman for St. Elizabeth's Hospital in Brighton announced 15 police officers were taken to the emergency room for "injuries sustained in last night's police activity" related to the marathon bombing investigation.
- Friday - April 19 [9:30 a.m. PT]: Massachusetts National Guard arrived on scene to provide aviation support as the police activity intensifies in Watertown.
- Friday - April 19 [8:30 a.m. PT]: Massachusetts State Police say the brothers were in the Honda CRV when they carjacked the Mercedes SUV. For a while, each drove one of the two vehicles, but then ditched the Honda and reunited in the Mercedes.
- Friday - April 19 [8:25 a.m. PT]: The suspects' uncle, Ruslan Tsarni, spoke to reporters outside his Maryland home. Referring to the brothers as "losers," Tsarni said his nephews put a shame on the entire Chechen ethnicity. "Of course we're ashamed. Yes, we're ashamed," he told reporters.
- Friday - April 19 [8 a.m. PT]: Increased police presence seen in Watertown, Mass., and outside suspect's home in Cambridge, Mass. SWAT teams, bomb units, and heavily armed officers on the scene in both locations.
- Friday - April 19 [7:35 a.m. PT]: The University of Massachusetts Dartmouth said it closed its campus and ordered an evacuation after confirming that Dzhokhar Tsarnaev is registered there. The school said it closed the campus "out of an abundance of caution" as the search continued.
- Friday - April 19 [7:30 a.m. PT]: ABC News confirmed that investigators found the suspect vehicle in Boston unoccupied. They said authorities were combing the car for evidence.
- Friday - April 19 [7:25 a.m. PT]: Law enforcement officials confirm that suspect Dzhokhar Tsarnaev, 19, was born in Kyrgyzstan and is of Chechen ethnicity. His family lives in the restive Dagestan region of Russia.
- Friday - April 19 [7:00 a.m. PT]: Connecticut State Police were told by Boston authorities that the surviving bombing suspect may be traveling in a gray Honda CRV with Massachusetts license plate 316-ES9.
- Friday - April 19 [6:45 a.m. PT]: President Obama was briefed on the manhunt by Attorney General Eric Holder and FBI Director Robert Mueller between 9:45 a.m. and 10:45 a.m. ET this morning, say White House sources.
- Friday - April 19 [6:40 a.m. PT]: The father of the two Boston bombing suspects tells ABC News he spoke to one son Thursday to ask whether they were safe after the marathon incident. "Everything is good daddy, everything is very good," one of the sons told his father, making no indication they were involved.
- Friday - April 19 [5:30 a.m. PT]: FBI releases new photo of the remaining suspect, Dzhokhar Tsarnaev, who Boston authorities describe as "prepared to die." Investigators said he was heavily armed with bombs, rifles and other weapons.
- Friday - April 19 [5:20 a.m. PT]: All taxi service in the city of Boston was suspended pending further notice.
- Friday - April 19 [5 a.m. PT]: Boston's police commissioner says all of Boston must stay in their homes as the search for the surviving suspect in the bombings continues.
- Friday - April 19 [3:35 a.m. PT]: SWAT officers descend on Watertown, Mass., and surrounding areas. Boston-area universities and public schools are canceled for the day.
- Friday - April 19 [2:50 a.m. PT]: Authorities prompt "shelter in place" advisory for residents in Watertown, Newton, Waltham, Belmont, Cambridge, Arlington and the Allston-Brighton neighborhoods of Boston. All mass transit was shut down.
- Friday - April 19 [1:30 a.m. PT]: Massachusetts state and Boston police held a brief news conference, telling eastern Watertown residents to remain in their homes. Authorities confirmed that the carjackers are the same men wanted in the marathon bombings.
- Thursday - April 18 [Shortly after 7:30 p.m. PT]: Two armed men reportedly carjacked a Mercedes-Benz SUV in Cambridge. The carjack victim told authorities the suspect told him they were responsible for Monday's marathon bombings.
A police pursuit got under way for the carjack suspects, who fled to Watertown, just west of Cambridge. During that chase, investigators say explosives were thrown from the SUV in an attempt to stop police. A gun battle erupted between the carjackers and police, during which a transit police officer, later identified as Richard Donohue, was injured.
One of the suspects, later identified as suspect No. 1 (26-year-old Tamerlan Tsarnaev) in the Boston bombings, was shot and killed during the exchange of gunfire. The second suspect, 19-year-old Dzhokhar Tsarnaev, got away, triggering a massive manhunt.
- Thursday - April 18 [7:30 p.m. PT]: An MIT campus police officer was found shot multiple times in his vehicle. He was responding to a disturbance on campus. Law enforcement officials told ABC News that it appears the officer, identified as 26-year-old Sean Collier, was ambushed and killed in cold blood while sitting in his parked car by the Boston Marathon bombing suspects.
- Thursday - April 18 [7:20 p.m. PT]: Shots were fired on the Massachusetts Institute of Technology in Cambridge, just outside Boston.
- Thursday - April 18 [2 p.m. PT]: Investigators released photographs and video of the two suspects and asked for the public's help in identifying the men.
- Monday - April 15 [11:50 a.m. PT]: Two bombs exploded at the finish line at the Boston Marathon, killing three people and injuring more than 180 others.
The Associated Press and ABC News contributed to this report.