In Mali, armed men killed at least 40 people in two villages Monday in the latest deadly attack to hit the country amid mounting ethnic tensions between Dogon and Fulani fighters. The mayor of one of the villages, which are populated by ethnic Dogons, says around 100 gunmen on motorbikes stormed both towns, opening fire at residents. The attack comes just a week after another deadly raid on a Dogon village. In March, suspected Dogon militias killed over 150 Fulani in two villages in central Mali. The U.N. warned earlier this month that the atrocities in central Mali are likely to continue unless immediate action is taken.