Effacer le tableau ("erase the board") was a military operation conducted during the Second Congo War by the Movement for the Liberation of the Congo (MLC) and the Rally for Congolese Democracy-National (RCD-N) against the government-aligned Rally for Congolese Democracy-Movement for Liberation (RCD-ML). The operation ran from October 2002 to January 2003 and sought to capture the town of Mambasa in Ituri District, along with surrounding areas, as part of a broader push toward the city of Beni in North Kivu.
Mambasa, a town of roughly 20,000 to 25,000 residents at the time, sat in eastern Ituri, a region Human Rights Watch described in 2003 as "the bloodiest corner" of the DRC. The MLC troops involved became known locally as "les effaceurs" ("the erasers"). MLC forces were led by President Jean-Pierre Bemba, and RCD-N forces were led by Roger Lumbala.
According to Minority Rights Group International, the operation's conduct — including arbitrary executions, rape, torture, and forced disappearances directed at the civilian population, with the Bambuti pygmies singled out for mass killing and severe deprivation of fundamental rights — "may support a possible prosecution for genocide." The Bambuti were reportedly regarded by the rebels as "subhuman," and some rebels believed that Bambuti flesh held "magical powers"; senior officers cited biblical passages, including Deuteronomy 20:13–20:17, to justify these beliefs. Summary executions also targeted members of the Nande people.
The campaign in Mambasa unfolded in three phases. On October 12, 2002, MLC/RCD-N forces captured Mambasa under the command of Colonel Freddy Ngalimu, subjecting the town to looting, mass rape, destruction, and violence. At the end of October, RCD-ML troops recaptured Mambasa. In November and December, MLC/RCD-N forces recaptured the town again, this time under Colonel Widdy Ramses Masamba. Both Ngalimu and Masamba reported to General Constant Ndima Kongba, according to a UN-mandated mission; Ndima was nicknamed "Effacer le tableau" and was part of a group of the same name, though the MLC stated in 2021 that Ndima did not take part in these operations.
Reports described widespread cannibalism during the campaign. Estimates place the number of Pygmies killed at 60,000 to 70,000, with more than 100,000 displaced. Investigations found that attacks on the Bambuti extended beyond the effaceurs and became common among multiple armed forces during the Second Congo War.
In March 2016, the International Criminal Court convicted Jean-Pierre Bemba, the DRC's vice president and MLC leader during the campaign, of war crimes and crimes against humanity in relation to conduct in the Central African Republic. That conviction was fully overturned on appeal by the ICC in June 2018.