A truckload of fireworks intended for Lunar New Year celebrations went off Friday in a massive, deadly explosion that destroyed part of an elevated highway in central China, sending vehicles plummeting 30 metres to the ground.

The official Xinhua news agency, citing provincial fire officials, reported five confirmed deaths but said only six of the 25 vehicles smashed in the collapse had been recovered.

An 80-metre stretch of a major east-west highway in Henan province collapsed in the explosion. It scattered blackened chunks of debris and shattered the windows of a nearby truck stop.

Rescuers work at the accident site where an expressway bridge partially collapsed due to a truck explosion in central China's Henan Province. (Xiao Meng/Xinhua/Associated Press)

A Communist party spokesman for the nearby city of Sanmenxia, Nie Jianying, cited provincial officials as saying that five people were confirmed dead and eight hospitalized. Earlier reports by China National Radio and some other outlets of up to 26 people killed were removed from websites.

Photos posted on the website showed a stretch of elevated highway gone, with one truck's back wheels perched at the edge of a shorn-off section of the highway. Other photos showed firefighters below spraying water on scorched hunks of concrete, wrecked trucks and flattened shipping containers.

There was no immediate word on the cause of the explosion. It occurred about 90 kilometres west of Luoyang, an ancient capital of China known for grottoes of Buddhist statues carved from limestone cliffs.

Fireworks are an enormously popular part of Chinese Lunar New Year festivities. To meet the demand, fireworks are made, shipped and stored in large quantities, sometimes in unsafe conditions.

A result is periodic catastrophe: In 2006, on the first day of the Lunar New Year, a storeroom of fireworks exploded at a temple fair in Henan, killing 36 people and injuring dozens more. In 2000, an unlicensed fireworks factory in southern China exploded, killing 33 people, including 13 primary and secondary school students working there.