Seven Nigerian peacekeepers were killed Friday in an ambush in southwestern Ivory Coast, and more may be in danger, U.N. Secretary-General Ban Ki-moon said.
"These brave soldiers have died in the service of peace," he said. "I condemn this attack in the strongest possible terms."
The blue-helmeted peacekeepers were part of the U.N. Operation in Cote d'Ivoire on patrol in the town of Tai, near the border with Liberia, where threats of attacks against civilians have prompted the operation to strengthen its presence, the United Nations said in a statement.
Ban called on the government of Ivory Coast "to do its utmost to identify the perpetrators and hold them accountable."
He added that he understood that other peacekeepers remained in danger.
"Even tonight, after the attack, more than 40 peacekeepers remain with the villagers in this remote region to protect them from this armed group," he said.
U.N. peacekeepers have been in Ivory Coast since 2004. They remained after the 2010 presidential election, when the country was thrown into crisis after incumbent President Laurent Gbagbo refused to acknowledge defeat to former Prime Minister Alassane Ouattara.