Dozens of people are reported to have died after a bus plunged off Bolivia's infamous 'Road of Death' near the capital, La Paz.

The government is replacing the road, which winds down from the Andes mountains into the Amazon jungle.

But there are fears that the death toll will increase before the opening of the new highway, set for the end of the year.

It is also expected that tourists will continue to flock to the road which has earned the title of the most dangerous in the world.

The single-lane mud-covered road is being promoted as an ideal spot for extreme mountain-biking, even before the trucks and buses heading between La Paz and Coroico get an alternative route.

In the latest accident, a bus believed to have been carrying more than its permitted 45 people, slid off the road in early morning fog and plummeted 170 metres down a ravine.

Scores of people have died in accidents on the road this year

Rescue workers persisted through driving rain at the crash site north of La Paz, pulling bodies out of the wreckage and trying to find survivors.

Police Captain Damian Cruz told local radio: "We know there are about 25 dead.

"We're praying there won't be any more."

At least 65 people have been killed already this year on the steep road bordered by cliffs and ravines.

Reports from Bolivia say it is common to see buses and tractor-trailers winding their way along the road, teetering on the edge of abysses almost always hidden in heavy fog.