Al Qaeda in the Islamic Maghreb (AQIM) released a video of a Swiss nun who had been kidnapped in northern Mali nearly three weeks ago in the first claim of responsibility for the hostage-taking, according to SITE Intelligence Group.

The video, which outlined the conditions for the release of Beatrice Stockly, a Swiss missionary who was based in Timbuktu, is the latest indication of deteriorating security in Mali's north just months after a peace accord was signed.

Stockly, who had been kidnapped once before in 2012, appeared in a veil and stated the clip was filmed on Jan. 19 in the eight-minute video, which could not be independently verified.

"We, al-Qaeda in the Islamic Maghreb, the Sahara region, declare our responsibility for the kidnapping of this Christianizing kaffir Beatrice Stockly, who by her work, drove out many from the fold of Islam by seducing them with crumbs of this worldly life," said an English-speaking fighter.

The video also outlined the terms of the group's demands, which included the release of members imprisoned by the Malian government and Ahmad Al Faqi Al Mahdi, who is in the custody of the International Criminal Court.

Mali's expansive north has been unstable since 2012, when separatist rebels and jihadists seized the area. Although French forces scattered them from cities the following year, they have stepped up attacks in recent months.

AQIM claimed responsibility for a November assault on a Bamako hotel in which gunmen took hostages and killed 20 as well as an attack on Jan. 15 on a Burkina Faso hotel and restaurant in which armed assailants took hostages and killed 30.