UTHAI SAWAN, Thailand (AP) — Makeshift furnaces made of clay bricks were being built Monday on the grounds of Buddhist temples in a town in northeastern Thailand to cremate the bodies of the mostly young victims of last week’s massacre at a day care center by a former policeman.

Last Thursday’s brutal gun and and knife attack on the Young Children’s Development Center in Uthai Sawan left 36 people dead, including 24 young children. It was the biggest mass killing by an individual in the country’s history.

Phra Kru Adisal Kijjanuwat, abbot of the Rat Samakee temple, around 3 kilometers (2 miles) from the scene of the bloodshed, said 19 victims will be cremated in a group ceremony on Tuesday, bringing an end to a three-day mourning ceremony for the families.

He said the bodies would be cremated at the same time on charcoal-fueled open-air pyres to spare the families from having to wait long hours for successive ceremonies to be completed.

“We only have one furnace at the temple and we wouldn’t be able to cremate all victims at the same time, and I do not wish for any family to have to wait for a lengthy cremation process,” Adisal said.

“After seeing their grief, I thought it would be better if we can hold the ceremony at the same time and that all relatives can go through this final stage of this painful event together,” he said.

The monk said temporary furnaces were also being installed at two other nearby temples that will account for the remaining victims. He said that five families have chosen to host their funeral services separately from the group ones.

Police identified the perpetrator of the massacre as Panya Kamrap, 34, a police sergeant fired earlier this year after being charged with a drug offense.

A clear motive for the killings may never be determined after Panya took his own life, but police say they consider his financial and marital problems, as well as his history of drug use, to be factors.

Panya was cremated Saturday in a neighboring province after temples in Uthai Sawan refused to host his funeral, Thai media reported.