A Chadian peacekeeper shot and killed two colleagues and wounded a third in an attack in northern Mali, the U.N. mission said Sunday.
A soldier was arrested in the shooting Saturday in Tassalit, in the Kidal region, U.N. spokeswoman Radhia Achouri said. She said there was no known motive to the shooting.
Achouri said an investigation is underway.
It is the second shooting incident in less than three weeks. On February 25 in Kidal, a soldier among the Chadian troops killed a commander and a doctor with the U.N. mission after weeks of tensions over living conditions and pay.
The U.N. mission in Mali was deployed in July 2013 to the country in an effort to oust Islamist militants who had taken over vast stretches of northern Mali. The mission has been one of the international group's deadliest peacekeeping missions.
The U.N. forces in northern Mali have come under frequent attack from militants.
In early February, militants struck a U.N. peacekeeping camp in Kidal, killing at least six peacekeepers and wounding 30 others. And in November 2015, militants struck a luxury hotel in the capital Bamako, which left 20 people dead.
About 2,000 Chadian soldiers have taken part in peacekeeping missiong. But in recent years, dozens of the Chadian troops have deserted over pay and living conditions.
Some material for this report came from AP and AFP.