Cameroonian soldiers killed 20 Boko Haram fighters on Wednesday, March 16 during a raid in northern Nigeria carried out by a multinational force tasked with stamping out the Islamist militants, Reuters cited military sources as saying.

Cameroon commander General Jacob Kodji said the Islamist fighters were killed in the Nigerian town of Djibrila, which is about 10 km from the Cameroon border.

A spokesman for Cameroon's Defense Ministry, Colonel Didier Badjeck, said 12 hostages were freed and munitions and armored vehicles were seized during the operation.

Besides, Cameroon has sentenced 89 members of Nigerian militant group Boko Haram to death, Newsweek said.

Some 850 alleged members of Boko Haram, which pledged allegiance to the Islamic State militant group (ISIS) in 2015, are being detained in Cameroon, according to the BBC’s Hausa service. The executions are the first since a new anti-terror law was enacted in 2014 in Cameroon, which is part of a multinational force along with Nigeria and others aimed at combating the group’s spread in West Africa.

Boko Haram wants to establish an Islamist state in northeastern Nigeria and has waged a six-year campaign of violence to that end, killing thousands of people and displacing two million others, Reuters says.

Boko Haram is thought to have killed around 15,000 people, according to U.S. military figures.