A 6.6-magnitude earthquake struck central China on Monday, reportedly killing at least 75 people and collapsing many homes.
The U.S. Geological Survey said the quake hit in Gansu province about eight miles east of Chabu at 7:45 a.m. Beijing time (7:45 p.m. ET Sunday). The USGS recorded it at 6 miles deep and said it caused shaking in a rural region where the infrastructure isn't seismically resistant.
State news agency Xinhua said the death toll had risen to 75. It put the number of people injured at 600.
Photos posted on Chinese social media showed roads on the sides of riverbanks that had subsided and farmhouses reduced to piles of red bricks, Reuters reported.
"Many have been injured by collapsed houses," a doctor surnamed Du told Reuters.
The official China Meteorological Administration warned that heavy rain was possible in southeastern Gansu province Monday night and into Tuesday. It said the rain could hamper rescue efforts and urged residents to be alert to flash flooding in areas damaged by the earthquake.
About 5,600 residential buildings were damaged, the Beijing-based China Daily newspaper reported Monday afternoon. Some train service was suspended, and hundreds of armed police were mobilized to repair a damaged part of the main highway linking Lanzhou, the provincial capital, to Minxian county, it reported.
Xinhua said the quake was felt in the neighboring cities of Dingxi, Longnan and Tianshui, as well as Lanzhou, more than 100 miles away. About 19,000 people live in the area that was subject to the strongest shaking, it said.
The quake was followed an hour and a half later by a 5.6-magnitude quake at about the same depth, the USGS reported.
Based on the history of earthquakes of this size in rural China, there could be "significant casualties," the USGS said.
Gansu abuts Sichuan province, where a 6.6 quake in April killed 164 people and injured more than 6,700, China's worst quake in three years.