On Monday, April 15, Chechen-born Tamerlan Tsarnaev and his younger brother Dzhokhar placed and detonated two shrapnel-packed pressure cooker bombs near the finish line of the 2013 Boston Marathon, killing three and hospitalizing over 200 others. As well, the two murdered a policeman, while trying to avoid capture. If the two had not been stopped when they were, according to the FBI, the brothers were headed for New York City to create further carnage. The motivation for the attacks were the brothers' religious beliefs.
During preliminary interviews, following his arrest and the death of the older brother, Dzhokhar Tsarnaev told authorities that the bombing had been carried out to "defend Islam," which he said his brother believed was itself under attack by the United States. What brought the two former refugees to the point of plotting to brutally murder innocent civilians in their adopted country has been a matter of speculation. However, there are some relevant pieces of information that could be used as a basis to form a valid opinion on the matter.
On January 12, 2012, Tamerlan Tsarnaev, flew into Moscow, Russia and, from there, spent the next six months travelling to locations in Chechnya and Dagestan, two areas known for heavy militant Islamic activity and both home to terror cells. While in Dagestan, Tsarnaev was seen making six visits to a known militant at a mosque. Previously, in 2011, Russian authorities had asked the FBI to investigate Tsarnaev for possible links to extremist groups.