A chartered bus overturned in eastern Thailand’s Prachinburi province early Wednesday, killing 18 people and injuring 31 during an overnight journey from northern Thailand to Rayong for a municipal study tour.

Axar.az, citing AP, reports that authorities are investigating the accident and plan to intensify safety inspections on public transport.

Thailand ranks ninth globally in road traffic deaths, according to the WHO.

This incident follows other deadly crashes, including a bus fire in October that killed 23 students and teachers and a December crash in Prachuap Khiri Khan that left 14 dead, possibly due to driver fatigue.