The Boston marathon bombing was a terrorist attack which occurred on April 15 2013, during the annual Boston marathon. The bombing created an ensuing chase for the perpetrators and involved a deserted urban environment of historic size as the manhunt for the perpetrators was underway.
On the day of the bombings, officials swept the area of the marathon twice for any bombs before the explosions. People were allowed to come and go in the area as well as carry bags.
Two hours after the winners crossed the finishing line, but with the race still on going, two bombs exploded near the finishing line about 190 meters apart; the second bomb exploded 13 seconds after the first one. The bombing killed 3 people and injured a further 264, with at least 13 people requiring amputations.
An investigation was quickly launched shortly after the bombings. Nearly two days after the bombings, FBI agents identified two male suspects after trudging through countless videos and photographs. Once they were identified as two btoehrs: Dzhokhar Tsarnaev and Tamerlan Tsarnaev, and known to be in the Boston area, a historic of the lockdown of the city occurred.
Schools were closed, public transportation close, people were advised to stay indoors and military-style vehicles patrolled the streets. The police were also conducting a door-to-door search of the area.
Tamerlan was killed in the chase by his own brother, when he accidentally ran him over. After the police called off a search of the area, a local resident went out of his house to check on his boat when he discovered blood and a person inside. He notified the police and they took Dzokhar into custody.
After Dzhokhar was taken into custody, investigators started to understand the motives for the attack. Dzhokhar and his brother carried out the bombings in retaliation for US wars in Muslim countries. The brothers did not have any affiliation to terrorist groups, instead they were radicalized by online material. They learned how to build pressure-cooker bombs from terrorist guides online.
The trial of Dzhokhar began on 4 March 2015, nearly two years after the bombings. Dzhohar plead not guilty to all 30 charges against him, which included using and conspiring to use a weapon of mass destruction resulting in death, which carries a death penalty. On April 8 2015 Dzhokhar was found guilty on all thirty counts and was handed the death sentence on June 24 2015.