premise: Tamerlan Tsarnaev had a sister.
hypothesis: Tamerlan Tsarnaev . was a terrorist who , with his brother Dzhokhar Tsarnaev , planted bombs at the Boston Marathon on April 15 , 2013 . According to the federal indictment , during the shootout Tsarnaev was captured but died , partly as a result of his brother driving over him , and an MBTA police officer was critically injured in the course of Dzhokhar 's escape in the SUV ( the latter by what may have been friendly fire ) . During his incarceration , Tsarnaev 's brother allegedly said during questioning that the pair next intended to detonate explosives in Times Square in New York City . Dzhokhar reportedly also said to authorities that he and his brother were radicalized , at least in part , by watching Anwar al-Awlaki lectures .