The gunmen had seized about 170 hostages this morning at the Radisson Blu Hotel. Military commander Modibo Naman Traore told The Associated Press that about 20 hostages were freed later in the morning.
It was not immediately clear why the group was freed or how many exactly remained held by the militants.
Traore said 10 gunmen stormed the hotel shouting "Allahu Akbar," or "God is great," in Arabic before firing on the guards and taking hostages.