Three floors of the Westgate Mall in Nairobi collapsed during efforts to clear terrorists who had laid siege to the building for four days, trapping bodies inside, President Uhuru Kenyatta said in a televised address Tuesday. Five of the gunmen were killed in the fighting, Kenyatta said. Eleven other people had been arrested over possible connections to the attack, which left 61 civilians and six security officers dead, 62 people in the hospital and Kenya's reputation as a bulwark of African stability in tatters. "We have ashamed and defeated our attackers," he said in the address, which capped a four-day ordeal in which Kenyan forces battled Al-Shabaab terrorists for control of the upscale mall. Earlier in the day, sporadic gunfire could be heard coming from the mall as authorities made their final sweeps through the building.