At least 500 people have been confirmed dead in Wenchuan County, the epicenter of Monday's earthquake that jolted southwest China's Sichuan Province.

A brigade of 200 armed policemen reached the county at 11:15 PM on Tuesday to carry out disaster relief work, another 470 are expected to arrive there Wednesday morning.

Quake caused more serious damage to nearby Longxi and Yingxiu townships than to the county seat.

Earlier Tuesday afternoon, about 30 soldiers arrived at Yingxiu Town of Wenchuan County and rescued about 300 injured.

"Once the weather is ok, the army will start dropping foods and medicines to the town," said Li Shiming, commander of the Chengdu Military Area Command.

The Defense Ministry said earlier that almost 20,000 soldiers and armed police had arrived in the quake-hit areas of southwestern Sichuan Province.

Another 30,000 soldiers were en route to the area by air, rail and road, and on foot, a ministry spokesman told Xinhua.

The navy also summoned 2,500 soldiers from the Marine Corps and they will go to quake-hit areas at any time.

The air force's 18 helicopters have served 28 tasks to drop 12.5 tons of foods and other relief material to Mianyang, Mianzhu and Pengxian on Tuesday, the military source said.

And 12 civilian passenger planes, summoned by the General Staff Headquarters of the People's Liberation Army (PLA), also served rescue missions.

The Air Force source said Tuesday evening that a group of 42 soldiers, belonging to a radar troop, have entered Lixian County, one of the worst-hit counties where roads were blocked and communications were cut off.

The groups of soldiers were serving for a mission in the region when the earthquake took place. They managed to resume contact with the headquarters through a broadcasting station Tuesday and are engaged in relief work, the source said.

"According to them, casualty and damage to the roads in Lixian are very serious," the source said.

A strong quake measuring 7.8 on the Richter scale struck Wenchuan at 2:28 PM on Monday. The tremor was felt in many other parts of the country. The disaster had caused more than 12,000 reported deaths by Tuesday evening in Sichuan alone.

(Xinhua News Agency May 14, 2008)