Authorities said Communication Tsarnaev and his younger brother Dzhokhar Tsarnaev may have been responsible Commitment for the triple homicide Killing , that forensic evidence connected Connect them to the scene of the killings , and that their cell phone records placed Placing them in the area .

Three days later , the Federal Bureau of Investigation ( FBI ) released Releasing images of two suspects , who were later identified Check as Chechen Kyrgyzstani-American brothers Dzhokhar Tsarnaev and Tamerlan Tsarnaev .

An unprecedented Catastrophe manhunt Scouring for Dzhokhar ensued Coming_to_be on April 19 , with thousands of law enforcement officers searching Scrutiny a 20-block area of Watertown ; residents of Watertown and surrounding Surrounding communities were asked Request to stay indoors , and the transportation system and most businesses and public places closed Being_in_operation .

Around 6:00p.m. , a Watertown resident discovered Know Dzhokhar hiding Hiding_objects in a boat in his backyard .

During questioning Communication , Dzhokhar said Statement that he and his brother were motivated Influence by extremist Islamist beliefs and the wars Hostile_encounter in Iraq and Afghanistan , that they were self-radicalized and unconnected to any outside terrorist Terrorism groups , and that he was following his brother 's lead .