In one of the world’s worst child death tolls in a massacre by a single killer in recent history, most of the children who died in Uthai Sawan, a town 500km northeast of Bangkok, were stabbed to death, police said.

The age range of children at the daycare centre was from two to five years, a local official told Reuters.

They identified the attacker as a former member of the force who was dismissed from his post last year over drug allegations and he was facing trial on a drugs charge.

The man had been in court earlier on Thursday and had then gone to the daycare centre to collect his child, police spokesman Paisal Luesomboon told broadcaster ThaiPBS.

When he did not find his child there, he began the killing spree, Paisal said.

“He started shooting, slashing, killing children at the Utai Sawan daycare centre,” Paisal said.

“It’s a scene that nobody wants to see. From the first step when I went in, it felt harrowing,”

Piyalak Kingkaew, an experienced emergency worker heading the first responder team, told Reuters.

“We’ve been through it before but this incident is most harrowing because they are little kids.”

A large van that police said contained bodies of 22 people, mostly children, was seen departing from a police station headed towards the city of Udon Thani, 80km away, where autopsies would be performed.

A Reuters photographer also saw late on Thursday the body of the shooter, Panya Khamrapm, being moved in a bodybag from a van to a police station in the province.

Photographs taken at the daycare centre by the rescue team and shared with Reuters showed the tiny bodies of those killed laid out on blankets.

Abandoned juice boxes were scattered across the floor.

“He was heading towards me and I begged him for mercy, I didn’t know what to do,” one distraught woman told ThaiPBS, fighting back tears.

“He didn’t say anything, he shot at the door while the kids were sleeping,” another woman said, becoming distraught.

Police said the attacker’s weapon was a 9 mm pistol and it had been obtained legally.

Thailand’s police chief said the perpetrator had tried to break into the premises and had mostly used a knife in the killings.

“Then he got out and started killing anyone he met along the way with a gun or the knife until he got home. We surrounded his house and then found that he committed suicide in his home,” Damrongsak Kittiprapas told reporters.

He said a few children had survived, without giving details.

About 30 children were at the facility – a pink, one-storey building surrounded by a lawn and small palm trees – when the attacker arrived, fewer than usual, as heavy rain had kept many people away, said district official Jidapa Boonsom, who was working in a nearby office at the time.

“The shooter came in around lunch time and shot four or five officials at the childcare centre first,” Jidapa told Reuters.

The attacker forced his way into a locked room where the children were sleeping, Jidapa said.

A teacher who was eight months pregnant was also among those stabbed to death, she said.

The massacre is among the worst involving children killed by one person.

In Norway, Anders Brevik killed 69 people, mostly teenagers, at a summer camp in 2011 while the child death toll in other cases include 16 at Dunblane in Scotland in 1996 and 19 at a school in Uvalde in the US this year.

In the Beslan school hostage crisis in Russia in 2004, 186 children were killed by a group of hostage takers.

Prime Minister Prayuth Chan-Ocha, in a statement on Facebook, called Thursday’s shooting a “shocking incident”.

The government said it would provide financial aid to the victims’ families to help cover funeral expenses and medical treatment.

Lifeline 13 11 14

beyondblue 1300 22 4636