Heavy rain in north-west China is disrupting rescue efforts in Zhouqu county, which was hit by a landslide on Sunday killing more than 1,000 people.
Hundreds more are still missing, with hopes of finding survivors fading.
Fresh mudslides have blocked a road being used to bring in supplies as well as blocking the Bailong river, forcing the water level to rise by 3m (10ft).
Emergency shelters have been flooded. Forecasters predict heavier downpours for the next two days.
As much as 90mm (3.5in) of rain was forecast for Friday, the National Meteorological Centre reported.
Thunderstorms overnight triggered mudslides that swept away six houses in a village near Zhouqu town, leaving three people missing.
The number of confirmed dead stands at 1,117, with more than 600 missing.
Rescue team leader, Cao Yimin, said they would not give up looking for survivors: "Our first priority is to save everyone that we can, if there is just a glimmer of hope, then we will not give up on the possibility."
One man who was trapped in the upper floor of a building was rescued late on Wednesday.
The BBC's Chris Hogg, who recently visited Zhouqu, says the rains have made the mud more unstable and the authorities face a dilemma: should they continue the search for survivors or concentrate on clearing the debris?
The continuing rain means that unless the sludge is cleared quickly there is risk of further disaster, our correspondent says.
Specialists in epidemic prevention and medical workers have been sent to the area, state media reports.
One of the main problems facing the government is getting all the relief materials to where they are needed, the BBC's Michael Bristow reports from Beijing.
The affected area is mountainous and has few roads. Some have been blocked by landslides, while officials said others are congested with heavy traffic.
The authorities also face a growing problem of where to house survivors. More than 1,000 homes have been damaged or destroyed and another 3,000 flooded.
More than 4,000 tents have been sent to Zhouqu county but the mountainous terrain means there is little open space to set up camps.