Wikipedia
The term Mai-Mai or Mayi–Mayi refers to any kind of community-based militia group active in the Democratic Republic of the Congo (DRC), formed to defend their local territory against other armed groups. Most were formed to resist the invasion of Rwandan forces and Rwanda-affiliated Congolese rebel groups, but some may have formed to exploit the war for their own advantage by looting, cattle rustling or banditry.
Groups that fall under the umbrella term "Mai Mai" include armed forces led by warlords, traditional tribal elders, village heads, and politically motivated resistance fighters. Because Mai Mai have had only the most tenuous internal cohesion, different Mai Mai groups allied themselves with a variety of domestic and foreign government and guerrilla groups at different times. The term Mai Mai does not refer to any particular movement, affiliation or political objective but to a broad variety of groups.
The Mai Mai were particularly active in the provinces in the east bordering Rwanda, North Kivu and South Kivu (the " Kivus"), which were under the control of the Rwanda-allied Banyamulenge-dominated rebel faction, the Rally for Congolese Democracy- Goma (RCD-Goma). While militias have long been common in the Kivus, particularly among the minority Batembo and Babembe ethnic groups, the recent wars and conflicts caused large numbers of town dwellers to form Mai Mai. Although the Mai Mai, either as a group or as individual groups, were not party to the 1999 Lusaka Accord meant to end the war, they remained one of the most powerful forces in the conflict and the lack of cooperation from some groups has been problematic for the peace process.