Twenty-seven people were killed and 287 injured in 278 road crashes on Tuesday, the first of the "seven deadly days" of the Songkran festival.
Chotnarin Kerdsom, interior deputy permanent secretary, said on Wednesday the Road Safety Centre and associated agencies reported road accidents nationwide on Tuesday.
A total of 278 road accidents were reported on the first day of the road safety campaign, causing 27 deaths and 287 injuries, Mr Chotnarin said.
Speeding was the biggest cause of accidents (35%), followed by cutting in front of other vehicles (25%).
Most accidents involved motorcycles (79%) and most crashes occurred on main roads (87%), followed by highways (48%).
Pathum Thani, Phetchabun and Loei had the most road deaths, with two each. Phatthalung had the most accidents, 14, and highest number of injuries, 18.
Disaster Prevention and Mitigation Department chief Boontham Lertsukheekasem said many people were leaving Bangkok to enjoy Songkran in their home provinces and traffic was building up. He urged motorists to strictly abide by traffic rules.
