<br /> Prosecutors on Thursday will urge a federal appeals court to uphold Boston Marathon bomber Dzhokhar Tsarnaev’s conviction and death penalty sentence. <br /><br />Tsarnaev, and his older brother Tamerlan, carried out the 2013 attack which killed three people and wounded more than 260 others. <br /><br />The U.S. Justice Department is expected to file a brief before the 1st U.S. Circuit Court of Appeals in Boston. <br />
