A powerful magnitude 6.0 aftershock hit quake-ravaged Sichuan on Sunday, killing two people, injuring over 480 and destroying 71,000 homes, AP reported. The aftershock was the most powerful recorded since the inital May 12 quake, whose death toll has risen to 62,664 with another 23,775 missing, according to the government. The aftershock hampers ongoing relief efforts to clear debris jamming rivers across the disaster area. This places 700,000 survivors at risk of flooding. A government ministry said 69 dams in Sichuan were in danger of collapse from quake damage, but reservoirs have been drained to lessen the risk.