What made it hard for the rescue teams to approach the earthquake zone? [origina

The most powerful earthquake to hit China in 30 years is feared to have killed thousands of people in the southwestern province of Sichuan. The official news agency Xinhua says more than 50,000 people may have died. [6]The authorities have launched a major rescue operation, but they are finding it difficult to reach victims because roads have collapsed.
    Our correspondent Nick Mackie has just arrived near the epicenter, north of the provincial capital Chengdu, in the middle of the night, when it is pitch-black, and there is no power at all in the town. Many of the buildings are badly damaged, some have collapsed and there were workmen and soldiers working away, trying to clear the debris from some collapsed buildings to see if there were people underneath.