NOWSHERA, Pakistan – The death toll in the massive flooding in Pakistan surged past 800 as floodwaters receded Saturday in the hard-hit northwest, an official said. The damage to roads, bridges and communications networks hindered rescuers, while the threat of disease loomed as some evacuees arrived in camps with fever, diarrhea and skin problems. Even for a country used to tragedy — especially deadly suicide attacks by Taliban militants — the scale of this past week's flooding has been shocking. Monsoon rains come every year, but rarely with such fury. The devastation came in the wake of the worst-ever plane crash in Pakistan, which killed 152 people in Islamabad on Wednesday. In neighboring eastern Afghanistan, floods killed 64 people and injured 61 others in the past week, while destroying hundreds of homes and huge stretches of farmland, according to Matin Edrak, director of the Afghan government's disaster department. As rivers swelled in Pakistan's northwest, people sought ever-shrinking high ground or grasped for trees and fences to avoid getting swept away. Buildings simply crumbled into the raging river in Kalam, a town in the northern part of the Swat Valley, Geo TV showed Saturday. Reports coming in from districts around the northwest, where such flooding has not been seen since 1929, showed at least 800 people had died, said Mian Iftikhar Hussain, the region's information minister. The U.N. estimated that some 1 million people nationwide were affected by the disaster, though it didn't specify exactly what that meant. Floodwaters were receding in the region, and many people remain missing, Hussain said. Over 30,000 Pakistani army troops engaged in rescue and relief work had evacuated 19,000 trapped people by Saturday night, said army spokesman Maj. Gen. Athar Abbas. "The level of devastation is so widespread, so large," he said. "It is quite possible that in many areas there is damage, deaths, which may not have been reported."