Driver Nguyễn Cảnh Hạ Long. — Photo courtesy of Gia Lai Police

GIA LAI — Police in the Central Highlands province of Gia Lai have detained the driver of a sleeper bus that overturned early Monday, killing four people and injuring 20 others, authorities and local media reported.

The provincial police investigation agency has ordered the temporary detention of Nguyễn Cảnh Hạ Long, 33, while investigating the cause of the crash.

The sleeper bus, carrying 33 people, overturned at about 3:10am on Monday on the western Pleiku bypass in Hội Phú Ward.

Hạ Long was driving from Hàm Rồng towards Đăk Đoa when the bus left the road and overturned.

Heavy rain, darkness and dense fog reduced visibility at the time. Mud had also washed onto the carriageway from both sides of the road, leaving a layer about 10cm thick and making the surface slippery, according to authorities.

The crash killed four people and injured 20 others. Fifteen of the injured passengers were discharged from hospital later on Monday, while five remained under treatment.

The road had not yet been officially handed over for management and operation, and some sections had not met regulatory conditions for opening to traffic.

It forms part of a project to upgrade National Highway 19 and had not been handed over to Gia Lai Province because some safety requirements remained unmet. Vehicles had nevertheless been using the route regularly, police said.

Police are continuing to investigate the cause of the crash and determine the responsibilities of those involved. — VNS