NIAMEY, Niger — U.S. service members are being evaluated for potential injuries after their vehicle activated an improvised explosive device in Niger on Saturday, according to officials from U.S. Africa Command.

No one was killed in the incident, which happened as the service members were riding a mine-resistant, all-terrain vehicle while entering a firing range near Oullam, according to a media release from Air Force Col. Christopher Karns, an AFRICOM spokesman.

The medical evaluations are precautionary, he said.

Karns said there were four service members in the vehicle, but he could not immediately say from what branch or unit.

Ouallam, in western Niger, is not far from where four U.S. soldiers died during an October 2017 ambush. That attack by Islamic militants also killed four Nigerien soldiers in the joint patrol force.

The ambush drew attention to the U.S. military’s role in training troops in Niger.

U.S. and Nigerien partner forces were conducting a training exercise when the Saturday explosion occurred, according to the release.

Nigerien partner forces have secured the scene and are assessing the incident.

“U.S. forces are in Niger to assist our African partners in their efforts to counter violent extremist organizations,” said Karns. “A safe, stable, secure and prosperous Africa is an enduring United States interest.”