In 1994, an influx of Hutu refugees from Rwanda fed the ongoing low-level violence between Congolese Hutu and Tutsi ethnic groups. In 1997, the armed forces of Rwanda and Uganda intervened in the ethnic conflict and contributed to a presidential coup, in which Laurent Kabila replaced president Mobutu Sese Seku as premier of the DRC. Subsequently, more neighbouring countries intervened and further escalated the violence, as they fought proxy wars on Congolese soil. Burundi, Rwanda and Uganda supported rebels opposed to the Kabila regime, while Angola, Chad, Namibia, Sudan and Zimbabwe assisted the government. The proxy war was declared over in 2003. However, violence has persisted in much of the east of the country. Despite some successes against the many armed groups operating in the east, most notably the March 23 Movement (M23), offensives against the Rwandan Democratic Forces for the Liberation of Rwanda (FDLR) and the Ugandan Allied Democratic Forces – National Army for the Liberation of Uganda (ADF–NALU) continue with patchy progress.