Cambodian Prime Minister Samdech Techo Hun Sen said Wednesday that seven more U.S. tear gas barrel bombs had been discovered in Southeastern Svay Rieng province, bringing the total number of chemical bomb locations found in the province to nine.

“Now, chemical weapons have been found in many locations in Svay Rieng province. At first, we thought that there were only two locations, but now, we found up to nine chemical bomb locations,” he said in a speech during a visit to some 14,000 garment factory workers in the Southwestern outskirts of Phnom Penh.

“These are the U.S. bombs that had been dropped in Cambodia more than 40 years ago,” he added.

According to the prime minister, Cambodian and U.S. anti-chemical weapon experts have been working together to remove the bombs.

The chemical bombs, containing 2-chlorobenzalmalononitrile (CS), a type of tear gas, were dropped from a U.S. warplane in 1970 during the Vietnam War era.

Authorities initially found two chemical bombs, weighing more than 200 kg each, in the complexes of a primary school and a pagoda in Koki village in Svay Rieng province in January.

Chemical bomb experts have begun an operation to remove them since last week, as hundreds of villagers living around the bomb sites have been evacuated at daytimes to a safe refuge.

Lieutenant General Ke Da, deputy secretary general of the Cambodian Defense Ministry’s anti-chemical weapons authority, told Xinhua earlier this month that the chemical bombs were very harmful to people’s health, and if the chemical leaked out, it would cause burning eyes, coughing, breathing difficulty, stinging skin, vomiting and cancer.

It is estimated that between 1965 and 1973 the United States dropped about 2.7 million tons of explosives on 113,716 locations in Cambodia.

According to Cambodian government figures, from 1979 to Sept. 2017, landmines and unexploded ordnance (UXO) had killed 19,757 people and either injured or amputated 44,948 others in the country. Source.