Dzhokhar Tsarnaev contributed to his wife 's death , indictment says . Counts involve alleged use of weapons of mass destruction and killing of MIT officer . Evidence : IEDs were made from pressure cookers , explosive devices , explosives , other items . An arraignment is set for September 10 in U.S. District Court .
Dzhokhar Tsarnaev contributed to his brother 's death , indictment says . Counts involve alleged use of weapons of mass destruction and killing of MIT officer . Indictment : IEDs were made from pressure cookers , explosive powder , shrapnel , other items . An arraignment is set for July 10 in U.S. District Court .