The victims receive treatment at Hùng Vương Gia Lai Hospital. — VNA/VNS Photo

GIA LAI — Three more people died on Monday after a sleeper bus overturned on a bypass of National Highway 19 in Gia Lai Province, bringing the death toll to four, according to information from the scene.

The accident occurred at about 3:10am in Hội Phú Ward as the bus was travelling in heavy rain.

One person died at the scene, while three others died later on Monday.

About 20 people were taken to Hùng Vương Gia Lai Hospital, about 5km from the crash site, for emergency treatment. Some of the injured were in serious condition. The death toll could rise as injured passengers remain under treatment.

The Việt Tân Phát sleeper bus, registered in HCM City and driven by 33-year-old Nguyễn Cảnh Hạ Long, lost control and overturned onto its side near the roadside.

Police said initial tests showed that the driver had no alcohol in his blood and tested negative for drugs. The bus had a valid roadworthiness certificate until December 2027.

Initial findings suggested that heavy rain had caused soil, sand and water to flow onto the road, making it slippery and contributing to the loss of control.

Local authorities and traffic police visited the injured and offered support to the victims.

Authorities are investigating the cause of the crash. — VNS