Uthai Sawan, Thailand - A former police officer fatally shot at least 37 people, at least 24 of them children, after bursting into a child day care center in north-eastern Thailand on Thursday, police reports said.

Thailand's deputy police chief Torsak Sukwimol initially put the number of dead at 34, with the number rising later to 37.

The horrific shooting took place in the town of Uthai Sawan, district of Nong Bua Lamphu Province, close to the border with Laos.

The assailant, armed with guns and knives, then fled the scene in a white pickup truck. He is reported by Thai media to have killed himself, along with his wife and child.

Twelve people were injured and the local hospital called for blood donations, according to a report in the Khaosod newspaper.

Citing the authorities, the Bangkok Post reported that the man had forced entry to the day care center and immediately opened fire.

The motive for the killings was unclear. Khaosod reported that relatives of the victims were distraught. It said the suspect had lost his position with the police on account of drug offenses.

Mass killings are rare in the largely Buddhist Thailand. In February 2020, a soldier killed 29 people after taking them hostage in a shopping center in Nakhon Ratchasima in the north-east of the country. He was shot and killed by security forces.