Police say hundreds of survivors have been pulled from the rubble
British aid agencies have started to co-ordinate emergency help after a powerful earthquake hit western China.
Chinese officials said at least 400 people died and thousands were feared injured after the magnitude-6.9 quake in Yushu county, Qinghai province.
Cornwall-based disaster relief charity ShelterBox has mobilised one of its response teams in China to the area.
The British Red Cross said its Chinese counterparts were sending 500 tents and clothing and quilts for 1,000 people.
ShelterBox said it was working to assess the areas of greatest need following the tremor 800km (500 miles) south-west of the provincial capital Xining.
General manager Lasse Petersen said: "The local officials are already saying the biggest problem they're facing is lack of tents.
"The situation of several villages higher up in the mountains is still unknown, and roads and communications have been cut.
"Reports suggest there's widespread destruction and we are liaising with our personnel in China to assess the need."
The Red Cross said an assessment team from Qinghai province was in the region, and more charity workers from Beijing would join them on Wednesday.
Wyndham James, Save the Children's director in China, said the charity was contacting organisations in the region and liaising with the Chinese government.
"We will decide shortly with our partners what help we should give and whether we should send in a team to help," he said.
ActionAid China's country director Keshav Gautam said: "In our experience of responding to earthquakes, most recently in Haiti but also in Sichuan in 2008, we know it will be vital to get medical supplies and essential items to Yushu county as fast as possible to help the survivors."
The Disasters Emergency Committee, an umbrella organisation of 13 British humanitarian charities, said it was monitoring the situation in China.
A spokesman said: "An emergency response co-ordinated by the Chinese government is already underway.
"The Chinese authorities have long experience of dealing with natural disasters and have not made an early call for international assistance."
Most of the buildings in the worst-hit town of Jiegu were wrecked, and landslides have cut off roads. Police said hundreds of survivors had been pulled from the rubble.
In 2008, a huge quake struck in neighbouring Sichuan province, about 800km from Yushu, which left 87,000 people dead or missing and five million homeless.