The death toll in the collapse of a section of a mountainside expressway in China's Guangdong province doubled to 48 on Thursday, the official media reported, as more than 20 vehicles tumbled down a slope.

The disaster involving a large number of vehicles was caused on Wednesday by a landslide at the Chayang section of the Meizhou-Dabu Expressway in Meizhou city on the first day of the five-day May Day holiday.

The collapsed section of the expressway measures 17.9 metres long and covers an area of 184.3 square metres.

So far 48 people were killed and several others injured, state-run Xinhua news agency reported. On Wednesday the death toll was 24.

The collapse happened on Wednesday early morning after a month of heavy rains in a mountainous part of southern Guangdong province. Vehicles fell down the slope and some caught fire, reports said.

Chinese President Xi Jinping has given “important instructions” on the rescue and disaster relief work following the fatal expressway collapse, the report said.

Xi instructed that every effort be carried out for on-site rescue, and treatment of the injured.

Efforts should be made to repair the damaged roads and restore traffic order as soon as possible, Xi said.

All regions and relevant departments must ensure the safety of people's lives and property and the overall social stability, he said.

Premier Li Qiang has also given instructions to spare no effort in rescuing the injured, carry out follow-up work, do everything possible to search and rescue trapped persons, and strictly guard against secondary risks.

Li emphasised that the ongoing May Day holiday is the peak of tourism prime time, accompanied by widespread rainfall in some areas, necessitating all-out efforts to prevent accidents and disasters.

The Ministry of Emergency Management, the Ministry of Transport and other relevant departments have dispatched working groups to the scene to conduct the rescue efforts.

Except for the headline, this story has not been edited by The Telegraph Online staff and has been published from a syndicated feed.