DISASTER STRIKES: Rescuers continue to search for survivors of China's worst earthquake in over 30 years, in spite of tough obstacles. Rocks and landslides are blocking roads to the affected regions, and heavy rains have grounded the helicopter relief effort. According to official state media, the death toll of the quake, 7.9 on the Richter Scale, is now more than 12,000 in the southwestern province of Sichuan. But that number is expected to rise, as thousands more are trapped under rubble. In one city, Mianyang, 18,000 people are still buried, with over 3,500 confirmed dead. Reports say that in another city, Beichuan, 80 per cent of buildings have been destroyed. Beijing has deployed 50,000 troops to assist with the relief effort. An official from China's Civil Affairs Ministry has said that the country welcomes foreign donations of money and supplies, but it is not ready to accept outside rescue teams, due to traffic restrictions. The powerful quake was felt 1,528km away in Beijing, which is set to host the Olympic Games in August. Residents there said they felt shaking for one full minute. But officials say no Olympic venues were affected.