BANGKOK, Jan. 23 (Xinhua) -- A pickup truck overturned in southern Thailand's Chumphon province, killing four Myanmar workers and injuring 12 others, local media reported on Wednesday.

The accident happened on Tuesday night when the pickup carrying Myanmar workers fell into a ditch and flipped over. The pickup was transporting the workers to Surat Thani province in the south.

The passengers were rushed to hospital and four of them were pronounced dead, police said. Among the 12 injured, six were in critical condition.

The driver was slightly injured and he said he lost control when approaching to ditch.

Witnesses said they saw the driver was racing against another truck's driver before the accident occurred.

Thailand has a bad record of fatal road accidents mostly due to the weak enforcement of driving rules.