Villagers from Svay Rieng province upset with land grabs in their area clashed with police Monday, leaving five injured.
Police beat protestors with electric and standard batons, residnets said.
Land grabs are an increasing problem in Cambodia and a major source of destabilization.
Over 200 families in this dispute face the loss of farmland.
Pen Sareoun, a Daung commune villager, said she was beaten with other family members.
"All of us have swollen arms," she said. "There are over 200 families in Trapeang Lepeak Thlok Priing with land right since 1979, growing corns, beans, sesame, potatoes, and cashew trees. Now the land has been cleared."
"Please Prime Minister Hun Sen and other officials in charge, help us people who are victims," she continued. "Please hear our plight; we are belittled. The tractors cleared the land and no one can protest."