BEIJING — Chinese rescuers searched for survivors through a mountain of rubble Wednesday after a landslide buried a residential block in southwestern China, killing at least 25 people, the official Xinhua news agency said.

Terrified residents had scrambled to flee the nine-floor building when the landslide struck Wulong county, about 125 miles outside the city of Chongqing, on Tuesday evening, a Wulong disaster relief official told Reuters.

The building was home to 25 families, but it was not clear how many were inside when the landslide struck after several days of heavy rain, the official said.

Xinhua said only seven people in the building were known to have escaped the disaster.

Chongqing television showed hundreds of police, soldiers and firefighters digging through a massive pile of boulders, concrete blocks and mangled girders and carrying away corpses wrapped in blankets.

Xinhua quoted a survivor, Xia Youming, describing the building's collapse.

"Suddenly I saw many stones rolling down from the staircases, followed by an ear-deafening sound," said Xia, who was standing in front of the block at the time.

"Seeing the building inclining to one side, I started to run for my life. But after just a few steps, I felt something hit my back. When I came to, I found I was on the hospital bed."