In 1985, Burkina Faso organised a general population census. During the census, some Fula camps in Mali were visited by mistake by Burkinabé census agents. The Malian government claimed that the act was a violation of its sovereignty on the Agacher strip. Following efforts by Mali asking African leaders to pressure Sankara, tensions erupted on Christmas Day 1985 in a war that lasted five days and killed about 100 people (most victims were civilians killed by a bomb dropped on the marketplace in Ouahigouya by a Malian MiG plane). The conflict is known as the "Christmas war" in Burkina Faso.