JOHANNESBURG (AP) — Mali’s military says 24 soldiers are dead in the latest extremist attack as alarm grows about the vast Sahel region as a haven for fighters linked to the Islamic State group and al-Qaida.

Monday’s attack comes amid a surge in assaults that have killed over 100 Malian troops in recent weeks.

A statement overnight says 29 soldiers were wounded and 17 extremists killed at Tabankort in the northeastern Gao region.

The attack occurred while soldiers from Mali and Niger carried out an operation along their border to track extremists. The statement says Nigerian troops detained about 100 suspects.

Mali’s statement does not say which extremist group was to blame.

Regional forces, French troops and a United Nations peacekeeping mission all are trying to contain the extremist threat.