A Thai teenager killed at least five people and himself at a school outside Bangkok on Friday after fatally shooting his grandparents, police said, in the Southeast Asian nation’s worst mass killing since 2022.

Police said the shooter, who was 14 years old, fired at least 26 bullets, and was found with 34 additional ammunition rounds. The gun had belonged to his grandfather, police said.

Students streamed out of the Debsirin Nonthaburi School, on the capital’s northwestern outskirts, as the wounded were loaded on to ambulances and teachers hugged each other and cried. In photos circulated by emergency workers, one person is seen lying down on a stretcher outside an ambulance, while another is attended to by a medic.

Police said 23 people were wounded in the incident, the latest in a succession of high-profile shootings in recent years in Thailand, which has by far the largest number of guns in civilian possession in Southeast Asia, and among the most per capita in Asia, according to a 2017 estimate by the Small Arms Survey.

One 18-year-old student told Reuters he initially thought there were firecrackers going off or someone banging an object.

“I didn’t think it was a gun at first,” he said. “There were many shots: bang bang bang. Then it went quiet. Then it started again.”

Second school shooting

Education Minister Prasert Jantararuangtong told Reuters that both teachers and students were among the casualties. The motive for the shooting was being investigated, he told reporters.

Police identified the perpetrator as a student. It is the second school shooting in Thailand this year after a teacher died and a student was injured in the south of the country in February.

Emergency worker Kiatikhun Verapongpradith, 47, described arriving as the shooting was ongoing and his team treated students with injuries in the back, chest and arms. They found a male teacher lying dead on an upper floor of the school, and in another room they found a female teacher with wounds in her chest and arm.

“We gave CPR for about 30 minutes and rushed her to the hospital as we could not get her heart rate up, but we tried our best,” he said.

He said he was called to treat the teenage shooter after hearing a final shot.

“We rushed up and found that the perpetrator had shot himself in the right side of the head and collapsed. When we got up there, we checked his pulse, he still had one, so we started CPR.” The suspect was then taken to the hospital, he said.

Traffic near the Debsirin Nonthaburi School in Nonthaburi was nearly at a standstill, an AFP journalist saw, with local media reporting that parents were picking up their children following the incident.

In the 2025 academic year, the school had an enrollment of around 3,100 students and 147 teachers, according to district authorities.

Deputy Education Minister Akkharanan Kannakittinan said in a statement he was coordinating to provide assistance.

“This is terrible for something like this to happen,” Prime Minister Anutin Charnvirakul told reporters. “I’m sad for those who died and sad for something like this to happen in our country.”

History of shootings

Gun ownership and gun violence are not uncommon in Thailand, which has seen a series of deadly shootings in the past six years, with children among the victims.

Thailand’s worst mass killing by a single perpetrator in its recent history took place in 2022, when a former policeman ran amok in a three-hour gun-and-knife attack in the northeast that killed 36 people, including 22 children stabbed as they slept at a daycare centre.

A gunman killed five people, including security guards and a vendor, at a Bangkok market in July 2025 before turning the gun on himself, while a teacher died in the southern city of Hat Yai in February this year when a shooter opened fire at a school where she worked.

In 2020, a soldier killed 29 people in a shooting rampage in Nakhon Ratchasima. And in 2023, a 14-year-old used a modified handgun to kill two people and wound five others at a luxury Bangkok shopping centre.

After the 2023 shooting, Anutin, who was then serving as interior minister, ordered a raft of gun control measures, including a short-term ban on new licenses, import restrictions, and banning of people under 20 years from shooting ranges.

Longer-term measures also included a medical certificate assessing the mental health and psychological condition of gun owners as well as a specified validity period for some gun licenses.

Thailand had an estimated 10.3 million firearms in civilian possession, equating to around 15 guns per 100 residents, the highest rate in Southeast Asia by a wide margin, according to a 2017 estimate by the Small Arms Survey.