Abidjan - Thousands of farmers who fled Ivory Coast's 2011 civil war are returning to find their land illegally sold, raising the risk of fresh violence, Human Rights Watch (HRW) said on Thursday.
Around 3,000 people were killed in the brief conflict that broke out after incumbent president Laurent Gbagbo refused to acknowledge defeat at the hands of his rival Alassane Ouattara in an election.
An estimated 200,000 Ivorians - mainly Gueres, an ethnic group considered loyal to Gbagbo - fled to neighbouring Liberia fearing reprisals by Ouattara's supporters.
When they returned, many found their land occupied, often by immigrants from Burkina Faso, said the New York-based campaign group.
"Gueres fled the crisis with only the barest of possessions and returned to find that their houses had been pillaged and burned," HRW wrote in a report published on Thursday.
"Tension over land dispossession is mounting in western (Ivory Coast), with residents often referring to it as a 'bomb' that may explode if the government does not quickly take action to ensure restitution to rightful owners," it said.
Western Ivory Coast, home to the country's richest farmland and its most productive cocoa plantations, has a long history of tensions related to land that often take on an ethnic dimension.
In a written response to the report, the government said it was aware of the problem and planned to support local government efforts to handle such cases. It said it set aside funds to demarcate boundaries in 1,300 rural villages.
Pro-Gbagbo militias, often composed of Guere youth, terrorised outsiders - immigrants from neighbouring countries and migrants from elsewhere in Ivory Coast - after a 2002-2003 civil war.
Gueres now complain they are victims of a revenge campaign, including land seizures by armed Ouattara allies.
But in most of the cases, land was illegally sold, usually by other Gueres misrepresenting themselves as the rightful owners, HRW said.
HRW said there was evidence some groups were already taking justice into their own hands.
On March 13 and 23, gunmen crossed in Ivory Coast from Liberia, where around 58,000 Ivorian refugees still live, and attacked two border villages, killing at least nine people, it said.
The raiders targeted individuals involved in purchasing land illegally, and the attackers also burned the houses of the Guere sellers and co-signatories on the deals, HRW added.
HRW documented 117 cases of dispossession, but said it thought thousands had been affected.