Contaminated water from a river in Kratie province has been blamed in the deaths of at least 10 ethnic Phnong people as of late Sunday, with nearly 140 others hospitalised and hundreds more families fleeing their homes for fear their ancestors are “angry” at them, officials said.

Phun Phea, police chief in Kantuot commune, said as of 4:30pm on Sunday, at least 137 people were receiving treatment in hospitals in Kratie province, while those in serious condition had been transferred to Calmette Hospital in Phnom Penh.

“I do not know what has caused the illness to the people,” he said. “But some people said that they had problems with water that had poisonous chemicals, and others said that [the deaths] are caused by their ancestors who are angry at them,” he said.

Following the death of the first victim in Aloch village on Thursday, Phnong ethnic villagers held a celebration on Friday, where they prayed, drank rice wine and sacrificed cows and buffaloes as offerings to their ancestors in order to ward off the “evil danger” from their villages, Phea said.

Provincial Governor Var Thorn said on Sunday that the deaths, which began on Thursday, occurred after villagers from Kantuot commune drank contaminated water from a small river, called Prek Te, which flows from Mondulkiri into the Mekong River. Prek Te’s water basin covers more than 4,000 square kilometres, according to the Water Environment Partnership in Asia.

Ly Sovann, spokesman for the Ministry of Health, said officials had collected water and rice wine samples to be tested, with results expected soon.

“We ask [people] to stop [drinking] and [selling] wine and stop the use of suspected water from the river there,” he said in a message. “Local authorities can supply clean water to the villagers.”

The ministry has installed a mobile clinic, with an ambulance on site, for referred patients.

Sickened villagers experienced symptoms such as stomach-aches, vomiting, numbness, fatigue and dizziness, while others fell unconscious after they drank the water from the river and an attached stream, according to a statement from the provincial Health Department.

“Please, all people who live along the stream . . . stop using or drinking the water from this stream temporarily to refrain from danger,” the statement reads.

Despite distribution of clean water to several villages, a total of 248 families in Kantuot commune have left their homes and sought refuge with relatives elsewhere, or in the forest, Phea said.

Rath Roeun said his wife, Chrue Ny, and niece had drunk water while helping cut vegetables to prepare food for the funerals, and soon after began to experience symptoms of poisoning. They both were transferred to Calmette Hospital.

“I think my wife and niece’s illness is caused from drinking [contaminated] water because people use chemical pesticides and chemical grass-clearing spray to protect their rubber and cassava plantation, and the rain has brought those kinds of chemicals into the canal,” he said.

Additional reporting by Yesenia Amaro and Alessandro Marazzi Sassoon

Updated: 6:55am, Monday May 7, 2018