Dzhokhar and Tamerlan Tsarnaev set off two pressure cooker bombs during the running of the Boston Marathon, killing three people and injuring 264 others.

Dzhokhar Anzorovich "Jahar" Tsarnaev is an American domestic terrorist and mass murderer of Chechen and Avar descent who, along with his older brother, Tamerlan Tsarnaev, planted pressure cooker bombs near the finish line of the Boston Marathon on April 15, 2013. The bombs detonated, killing three people and injuring 264 others. The two then intended to commit another bombing in New York City, but Tamerlan was killed and Dzhokhar was arrested beforehand.

Tamerlan Anzorovich Tsarnaev was a Russian-born terrorist of Chechen and Avar descent who, with his younger brother Dzhokhar Tsarnaev, planted pressure cooker bombs at the Boston Marathon on April 15, 2013. The bombings killed three spectators and injured 264 others.

The Boston Marathon bombing, sometimes referred to as simply the Boston bombing, was an Islamist domestic terrorist attack that took place during the 117th annual Boston Marathon on April 15, 2013. Brothers Tamerlan and Dzhokhar Tsarnaev planted two homemade pressure cooker bombs that detonated near the finish line of the race 14 seconds and 210 yards (190 m) apart. Three people were killed and hundreds injured, including a dozen who lost limbs.

A pressure cooker bomb is an improvised explosive device (IED) created by inserting explosive material into a pressure cooker and attaching a blasting cap into the cover of the cooker.

The 2013 Boston Marathon was the 117th running of the annual marathon race in Boston, United States, which took place on April 15, 2013. Organized by the Boston Athletic Association (B.A.A.), it hosted the second of the World Marathon Majors to be held in 2013 with over 23,000 runners participating. Lelisa Desisa won the men's race with a time of 2:10:22, and Rita Jeptoo won the women's with a time of 2:26:25. Hiroyuki Yamamoto won the men's wheelchair race in 1:25:32 and Tatyana McFadden won the women's in 1:45:25.