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.