Beijing  - China has agreed to Japan sending an emergency rescue team to help with efforts to save tens of thousands of people buried under rubble after a devastating earthquake, the foreign ministry said on Thursday.

"The Chinese government has agreed to the Japanese government sending professional rescue personnel to help with rescue efforts in the Sichuan earthquake disaster area," ministry spokesman Qin Gang said in a statement.

The Japanese team is believed to be the first foreign team that China has allowed into the area since a 7.8-magnitude earthquake destroyed thousands of buildings in Sichuan and other areas of south-western China on Monday.

Several towns close to the epicentre were nearly razed, a military relief officer said Wednesday, as the confirmed death toll rose to about 15,000.

At least 26,000 people were believed to be buried in collapsed buildings, while the official Xinhua news agency said more than 30,000 people were missing or out of contact in Sichuan's Shifang city alone.

Military helicopters began flying aid, medical personnel and relief troops to isolated settlements near the epicentre on Tuesday.

But the extent of the damage and casualties in the worst-hit county of Wenchuan, which has a population of 105,000, remained unclear.

A paramilitary officer who was one of the first outsiders to reach some of the worst affected areas on Tuesday said that several towns were almost razed to the ground.

Heavy rain had initially prevented helicopters from flying emergency aid to Wenchuan while troops were still trying to restore two badly damaged main roads to the county town.

The earthquake was felt in cities hundreds of kilometres away, including Beijing, Shanghai, Hong Kong and Bangkok. (dpa)