NIAMEY (Reuters) -One hundred people were killed on Saturday in attacks on two villages in western Niger, Prime Minister Brigi Rafini said following one of deadliest days in recent memory for a country ravaged by Islamist violence. Rafini announced the death toll in remarks broadcast on national television on Sunday from a visit to the zone, near the border with Mali. He did not say who was responsible for the attacks. Security sources said on Saturday that at least 70 civilians had been killed in simultaneous attacks by suspected Islamist militants on the villages of Tchombangou and Zaroumdareye. Niger has suffered repeated attacks by Islamist militants linked to al Qaeda and Islamic State near its borders with Mali and Burkina Faso, part of a wider security crisis in West Africa’s Sahel region. It has also seen tit-for-tat killings between rival ethnic communities that have been stoked by the jihadist violence and competition for scarce resources.