Mali risks being dragged into a "catastrophic spiral of violence" because of reprisal attacks, UN rights chief Navi Pillay warned the UN Security Council on Tuesday.
Pillay said human rights observers are now in Mali and called on all sides in the conflict to refrain from revenge attacks.
"As the situation evolves, attacks and reprisals risk driving Mali into a catastrophic spiral of violence," the UN human rights commissioner told a Security Council meeting on protecting civilians in conflict.
"I call on all parties to the conflict to abide by international human rights and humanitarian law, and to prevent retaliation," she said.
France sent troops to Mali one month ago to halt an advance by Islamist militants on the capital.
Th rebels were forced into desert and mountain hideouts by French and Malian forces in the north of the country but are now launching guerrilla attacks.
The Islamists have been accused of brutal abuses during their 10-month old rule over northern Mali, but Malian forces have also been accused of reprisal killings.
"Protection of human rights is key to stabilizing the situation," Pillay said. She said human rights investigators from her department started arriving in Bamako last week.