Swinging batons and bashing villagers, Vietnamese police dispersed dozens of members of the Ede ethnic group who were attempting to interfere with a drainage project they fear will discharge wastewater into a lake they depend on, sources told Radio Free Asia.

Three villagers were hospitalized and 12 were arrested, they said.

“They hit us, injuring seven people of whom three had to be hospitalized due to the injuries on their heads, mouths, ears and shoulders,” said a protester who requested anonymity for security reasons.

Ea M’ta lake in the southern province of Dak Lak will be the endpoint of a rainwater drainage system project proposed by the province’s Cu Kuin district, the provincial and district governments said.

But residents living nearby fear that in addition to rainwater, the project could also divert wastewater into the lake, which could harm the environment and flood surrounding areas.

Though a local government task force reviewed the project and said that no major damage to the ecosystem or to water resources would result from it, the protesters do not trust the review, they said.

The clash with the police, armed with batons and shields, occurred on Thursday and Friday.

A video filmed by a witness shows several dozen police officers confronting a similar number of residents, mostly women, carrying the Vietnamese flag. They were mostly speaking in the Ede language, but at times they also spoke Vietnamese.

“We are determined to stop the District People’s Committee from discharging wastewater into the lake,” someone in the video said. “We can sacrifice our lives for this.We will resolutely protect [the lake].”

The protester who spoke with RFA said that the police shoved down a woman who was two months pregnant, and broke the shoulder of another protester who passed out shortly afterwards.

Police also knocked down a man and kicked his head repeatedly until his ears and mouth began to bleed.

The three people who were hospitalized returned to their homes on Monday, according to the source. Those who were arrested were all released after signing a paper pledging that they would not return to the protest or face prison.

Radio Free Asia attempted to contact Bui Hong Quy, chief of staff of Dak Lak provincial People's Committee and the Cu Kuin district People's Committee to verify the source’s account, but received no response.

According to state media, the drainage system project with a total investment of nearly 36.7 billion dong (U.S.$1.53 million) was approved by Dak Lak People's Committee in 2019. The nearly 4 kilometer (2.5 mile) drainage canal would begin at the Cu Kuin District Military Command and terminate at the lake.

The Dak Lak People’s Committee’s task force reviewed the project’s impacts on the environment, safety, and living conditions. The review indicated that the project would not negatively affect the environment, land, climate, and water sources serving residents living in the surrounding areas, state media said.

Residents living near the lake, however, said the review did not reflect reality.

Y Quynh Buon Dap, a human rights and religious activist who lives in Thailand as a refugee, said residents were worried because the survey was not thorough and did not include areas that could be affected by the project in the future.

On April 20, authorities stated that they were determined to complete the final component of the project, and that all activities that would prevent its implementation would be seen as unlawful.