An activist with environmental NGO Mother Nature who has been documenting the impact of sand dredging in Kandal province’s Sa’ang district was temporarily detained yesterday for flying a drone without permission and for his community activism, a few hours after a meeting between locals and authorities to discuss the dredging.

Hun Vannak was detained yesterday by some 20 provincial police officers in Koh Kor village just after noon. Before his arrest, residents and local authorities had met at a villager’s home, where they aired their concerns over continued sand dredging and its impact on their livelihoods. They say the dredging has caused multiple riverbank collapses, damaging locals’ homes.

The villagers and Vannak also went to the Raka Khpos commune office to protest the ongoing dredging.

Vannak said he was questioned for hours about flying a drone without permission over the weekend, and about his work to help the communities affected by the sand-dredging operations. Before releasing him, officers asked him to sign a document that he said had three conditions: that he inform authorities about future drone flights, that he not get involved in “general government management” and that he not lead “illegal” campaigns that “put security at risk”.

“What they [did] is 100 percent harassment,” he said. “But I’m not afraid.”

In a statement, the Cambodian Center for Human Rights said police were accompanied by four to five uniformed representatives of the Leng Chin Group, one of four companies behind the dredging, at the time of his arrest.

For several hours, fellow activists had no idea where Vannak had been taken, or why he was being held.

Later in the evening, however, Lim Kimsor, a women’s issues coordinator for Mother Nature, said provincial authorities told them Vannak was arrested for allegedly flying a drone without asking permission.

Khim Chankiri, provincial deputy governor, confirmed that provincial police “invited” an activist from Mother Nature to their station today, but maintained he was not aware why. Chankiri added that authorities are trying to solve the sand-dredging problem for villagers.

“We are finding solutions for 15 families who are most affected by riverbank collapses in connection with Leng Chin Group company,” he said.

Kandal Provincial Police Chief Eav Chamrouen did not answer repeated calls, and other police officials couldn’t be reached to clarify why Vannak had been detained.

In June, two other Mother Nature activists were allegedly harassed by police in the same village after helping coordinate a protest over the same issue.

Fellow activist Ly Raksmey said Vannak had only attended the meetings yesterday to take photos and live stream the proceedings. “We did not expect that they would arrest him,” he said, adding that some 20 community members and Vannak’s family yesterday evening went to the police station to show their support.

Sorn Ramana, a project coordinator at the CCHR, said the organisation was “very concerned about this arrest as it follows a clear pattern of judicial harassment against Mother Nature activists”.