Note, if one reads further at the link, a "Jihadist" group are blamed for these killings. I don't think there are many Muslims in DR Congo. It could be a case, where, where there's a war, militias, Jihadists will take the opportunity to fight there. There was a story too, about al Qaeda supporting a group there.
Seven UN peacekeepers killed in eastern DR Congo fighting - France 24
Seven United Nations peacekeepers were killed in an operation against a rebel militia in the Democratic Republic of Congo's restive east, the UN said on Thursday.
Ten other peacekeeping troops were wounded, and another is missing, UN spokesman Stephane Dujarric said in New York.
Several Congolese were also killed or wounded in the joint operation, he said.
The deaths mark the biggest loss by the large UN force in DR Congo since the rebels killed 15 troops nearly a year ago.
Read more at: https://www.france24.com/en/20181115-democratic-republic-congo-united-nations-peacekeepers-kivu-beni-adf-ebola