JOHANNESBURG (AP) — The Islamic State group has claimed responsibility for an attack that killed 30 soldiers in Mali earlier this week.

A statement late Wednesday asserts that another 30 soldiers were wounded in Monday’s ambush.

The statement mentions no deaths among IS-linked fighters. Mali’s army has said 17 extremists were killed in the fighting at Tabankort in the northeastern Gao region.

Mali and Niger had been carrying out a joint operation along their border to track extremists. Nigerien troops detained about 100 suspects.

Well over 100 Malian soldiers have died in the past two months in attacks by fighters linked to IS and al-Qaida.

The U.S. says the Sahel region south of the Sahara Desert is of growing concern with thousands of IS-linked fighters active in Mali, Nigeria, Burkina Faso and elsewhere.