The United Nations' human rights office in Cambodia has condemned a government ruling that banned a peaceful march by people at risk of losing their land.
Early on Tuesday, dozens of armed riot police blocked several hundred representatives from delivering a petition to the home of the Cambodian Prime Minister, Hun Sen.
Sixty thousand villagers whose land is under threat across the country signed the petition, which calls on Hun Sen to help them.
Instead, the villagers were forced to hand over the petition to officials from Hun Sen's cabinet at a nearby park.
Land-grabbing is arguably Cambodia's most pressing problem, but a weak judiciary has proven no match for powerful interests behind the scourge.
The municipality banned the planned march late on Monday, but did not give a reason for doing so.
The United Nations' local human rights office described the ban as "regrettable", adding that it was given without reason or justification - and therefore contrary to the new law regulating demonstrations.