Four people were killed and six were injured in South Korea after elevated parts of a highway under construction collapsed on Tuesday, fire authorities said.

The National Fire Agency said 10 people were working on the site in the city of Anseong, about 65km (40 miles) south of the capital Seoul.

The accident took place at 9:49am (00:49 GMT), when five 50-metre (164-foot) steel structures supporting the highway bridge collapsed, trapping the workers in the rubble.

The cause of the collapse was not immediately known...

Hyundai Engineering, the builder of the site, apologised for the loss of lives and injuries.

“We are actively cooperating with the relevant authorities to ensure a swift site recovery and a thorough investigation into the exact cause of the accident,” the company said in a statement, according to the Yonhap News Agency.