Bad weather is hampering a massive rescue effort in China as the death toll from this week's earthquake passes 13,000.

Our correspondent Stephen McDonell reports from the quake zone in south-western Sichuan province that Chinese rescue workers have finally broken through to the site of the epicentre in Wenchuan county.

They made it on foot although without the heavy lifting equipment needed to dig through mountains of rubble in the devastated area.

State media is reporting the quake has killed 3,000 people in the city of Mianzhu alone.

According to some reports, in the city of Mianyang there are nearly 20,000 people buried.

Elsewhere in Beichuan County, photos show whole towns have collapsed, with only 20 per cent of buildings still standing.

Rescuers are still prioritising their efforts to try and reach possible survivors.

Later they will start the process of simply removing bodies and the death toll will rise sharply.

Apart from the human costs, the earthquake is having a tremendous impact on companies both foreign and local in the region.

For the first time, 56 companies trading on the Shanghai and Shenzen markets have been suspended because all power lines are down.

Rescuers parachute into quake zone
The Chinese military has resorted to a new tactic to get rescuers into remote earthquake devastated areas.

According to the Chinese airforce, troops are now parachuting into areas where bad weather has until now made it impossible to reach.

Wenchuan county was at the epicentre of a devastating earthquake, but until the troops got in little was known of the extent of its destruction.

Sixty-thousand people are unaccounted for there.

Elsewhere, the olympic torch relay continues in China but it will now start each day with a minutes silence.

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