Image copyright EPA Image caption Burnt out vehicles lined the street outside the chemical plant

At least 22 people have died and 22 more were injured in a blast outside a chemical factory in northern China.

A vehicle carrying chemicals exploded while waiting to enter Hebei Shenghua Chemical Co plant in Zhangjiakou, north of Beijing, initial reports suggest.

Photos from the scene showed dozens of burned out cars and trucks lining the street outside the plant.

Zhangjiakou is set to hold some ski and snowboard events when China hosts the 2022 Winter Olympics.

The blast occurred at 00:41 local time (16:41 GMT) in Zhangjiakou, a city some 200km (124 miles) northwest of Beijing. Thirty-eight trucks and 12 vehicles were engulfed by flames, city officials said.

Image copyright Reuters Image caption The blaze destroyed an electric bike

The injured were taken to hospital.

"On-site search and rescue work and investigation of the cause of the accident are still under way," the city's government said.

Factory officials said the plant had ceased production.

Despite its rapid economic development, China has struggled with industrial safety issues and chemical explosions occur regularly, the BBC's Stephen McDonnell reports from Beijing.

At least 19 people were killed in a blast at a chemical plant in Sichuan in July.

In 2015, 173 people died in an explosion at a chemical warehouse in the north-eastern port city of Tianjin. An official investigation into the blast found that corruption, political connections and official collusion allowed corners to be cut and safety systems to be overridden.