KANISHKA SINGH U.S. Capitol Police were aware of the possibility of violence from armed extremists when the Capitol was attacked by supporters of former President Donald Trump, but quickly became overwhelmed by "insurrectionists," the acting police chief said. Intelligence collected ahead of the January 6 assault on the Capitol suggested that the gathering would have the participation of armed "militia members, white supremacists, and other extremist groups," Yogananda Pittman said in prepared testimony to be delivered Thursday before the House Appropriations Committee. Pittman was the assistant chief of police of the department's Protective and Intelligence Operations on January 6 and…