In 2006 Déby won a third mandate in elections that the opposition boycotted. Ethnic violence in eastern Chad has increased; the United Nations High Commissioner for Refugees has warned that a genocide like that in Darfur may yet occur in Chad. In 2006 and in 2008 rebel forces attempted to take the capital by force, but failed on both occasions. An agreement for the restoration of harmony between Chad and Sudan, signed 15 January 2010, marked the end of a five-year war. The fix in relations led to the Chadian rebels from Sudan returning home, the opening of the border between the two countries after seven years of closure, and the deployment of a joint force to secure the border. In May 2013, security forces in Chad foiled a coup against President Idriss Déby that had been in preparation for several months.