Highways in the North and Northeast saw high traffic volume, as many people began the long trip back to Bangkok.

Banyat Jansena, deputy interior minister and the centre's deputy director, said on Sunday alone, there were 585 accidents resulting in 37 deaths and 650 injuries.

While most accidents (83 per cent) involved motorcycles, nearly half came from drunk driving, followed by speeding and suddenly cutting in front of other vehicles. Most accidents took place on straight stretches of secondary roads, and most occurred between 4pm and 8pm.

Buri Ram recorded the most deaths on Sunday with four, followed by Roi Et with three and Nakhon Phanom, Surin, Rayong, Chon Buri, Ubon Ratchathani, Kanchanaburi and Bangkok with two each.

Khon Kaen had the most injuries on Sunday with 25, followed by Surin's 24 and Chiang Rai's 23. Chiang Rai had the most accidents with 22, followed by Chiang Mai and Phetchabun with 19 each and Khon Kaen with 18.

Chiang Rai had the most cumulative accidents with 132 and the most injuries with 138, while Khon Kaen had the most cumulative deaths with 15.

Nationwide checkpoints stopped 1.88 million vehicles and arrested 43,783 violators, mostly for failing to provide a driving licence, not wearing a helmet and not using seat-belts.

In Chiang Mai, the Highway Police stopped and fined 200 motorists - most of them driving Bangkok-registered cars - for exceeding the speed limit.

With many people starting to head back for work in Bangkok or tourists returning to their hometowns, Chiang Mai's train station added three more carriages to each train, but tickets were still booked out until Thursday.

In Uttaradit, 27 extra checkpoints were set up along the Asia Highway, in anticipation of heavy traffic and potential lawbreakers.

In the north-eastern province of Nakhon Ratchasima, the Mitraparp Highway saw heavy traffic, and local bus terminals were packed with people trying to buy tickets.

Many north-eastern natives asked 890 elderly locals at a water-blessing ceremony in Kalasin's Muang district for a safe journey home. Bus tickets from the region were also sold out until tomorrow.

In Nakhon Phanom's Muang district, an inter-provincial air-conditioned bus overturned on the Nakhon Phanom-Sakon Nakhon Highway at 5.50am yesterday, killing three people and seriously injuring 13 others. Bus driver Thongyiam Rasawang had reportedly dozed off.

In Ayutthaya's Bang Sai district, a bus returning from merit-making activities in Ubon Ratchathani overturned, injuring 36 passengers. Police said the bus was returning to Samut Sakhon when the driver lost control at 5.30am yesterday.