Devastated families in Thailand gathered Tuesday to cremate their loved ones killed in a kindergarten massacre that killed 36 people – including 24 children.

The kingdom was stunned by the tragedy in north-eastern Na Klang province, one of the worst mass killings in its history, with flags flying at half-mast and King Maha Vajiralongkorn visiting victims’ families.

At Wat Rat Samakee temple in Na Klang, chanting monks began the ceremony as the exhausted and grieving close-knit rural community prepared to bid a final farewell to 19 of those killed.

“An incident like this should not have happened,” said Thanakorn Nueangmatcha, 39, before the funeral at the temple.

“They were just children.”

Other victims of the attack – perpetrated by a former police officer who killed his wife and child before taking his own life – are being cremated at other temples in the area.

At Wat Rat Samakee, incense and the fading scent of hundreds of flower bouquets hung in the air as volunteers continued to prepare the adjacent area for cremation.

The royal household-sponsored funerals will conclude three days of rites that began on Saturday.

Tuesday’s mass ceremony is highly unusual – bodies are usually cremated alone – but the area’s small local temples were overwhelmed by the number of victims.

Local media reported that makeshift ovens were also set up in other nearby temples.

The stumbling community reunited Monday as volunteers, soldiers and officials mixed cement and spread gravel to prepare a field inside the temple complex for the cremations.

They were working to build the pyres in the style of Thailand’s northeast, said Maemon Meeyuan, a grandmother of one of the victims.

“We’re doing it the old way,” she told AFP on Monday.

Prime Minister Prayut Chan-o-Cha has ordered an investigation, with police saying they intend to interview around 180 witnesses.

The attacker, 34-year-old former police sergeant Panya Khramrab, was fired from his post earlier this year on a drug charge, with locals claiming they suspect he is a methamphetamine addict.

However, preliminary testing revealed that he had no drugs in his system at the time of the attack.

At the temple ahead of the funeral, Comma Charoenchai, 75, said he was “still shocked” by the raid on the nursery.

But he said the community must “let the authorities handle the matter”.