Thai students in disbelief after deadly school shooting

Sobbing Thai students embraced each other tightly on Friday after a 14-year-old classmate entered their school wielding his grandfather's handgun and shot dead at least five school staff.

Tearful students in school uniforms held each other outside the Debsirin Nonthaburi secondary school while emergency workers treated injuries and parents looked for their children.

"I'm still in shock," 16-year-old Thatchai Jaiyen told AFP, expressing disbelief that a kind former teacher of his had been killed.

"She was such a good person. I thought that if she had encountered the shooter, she might have been able to reason with him.

"I never expected that the child would actually shoot her," he said, his voice trailing away.

The suspect first killed his grandparents at their home around 20 kilometres (12 miles) away with the same firearm, according to authorities.

He took his own life after killing a maths teacher, a Thai language teacher, a guidance counsellor, a student affairs administrator and a secretary at the school, according to police.

Debsirin Nonthaburi secondary is among the most prominent government schools in Nonthaburi province, just north of the capital Bangkok.

Grade 12 student Pakonkiat Sangchan was studying when he said he saw the shooter walking towards the building.

"My friend suggested that we start running, so that's what we did. We just ran," the 17-year-old said.

Prime Minister Anutin Charnvirakul told reporters that the boy's dead grandmother "used to be a teacher and she was quite strict on him about studying".

Student Purin Khumchoo said he felt the suspect was "a troubled kid" but had appeared "very professional" when he had aimed the gun at him at school on Friday.

"My group of friends who knew him said he was interested in the FBI and guns, and that he was bullied by many other students," the 17-year-old said.

Purin said he felt depressed and bad for the people who were killed.

"The two teachers who were killed were lovely, and many students became better people because of them," he told AFP.

Pawarisa Maylissa, a grade 12 student, said she was in a computer lesson when her teacher told the class about the active shooting.

They shut the classroom door, locked themselves inside and hid between tables, just before Pawarisa heard multiple shots fired.

At the home of the shooter's grandparents, a neighbour said she heard two loud bangs early on Friday morning.

"I didn't know if it was firecrackers or gunshots," said the woman, who declined to give her name. "I was shocked."

She said the grandmother had taught her son. Another neighbour said she had been his teacher at primary and secondary school.

Thriwit Sukkasampraset, 18, said the shooter "liked playing basketball in front of his house and walking his dog".

Thailand has one of the highest rates of gun ownership in the region and past promises of tightening gun laws have not prevented repeated shootings.

"I can't believe how a child like him could get access to a gun," Pawarisa said.

"I'm a bit worried that other kids might also have guns," she said.