N’DJAMENA (Reuters) - Boko Haram militants killed nine Chadian soldiers in an attack on a military camp on Friday in the north of the Central African country close to the Nigerian border, an army spokesman said on Saturday.

“On our side, there are nine dead and 28 wounded,” Colonel Azem Bermandoua told Reuters, adding that 28 militants were killed. The army said that Boko Haram carried out the attack.

Over the last seven years, Boko Haram has killed 15,000 people and displaced more than two million in its bid to create an Islamic state in Nigeria. A regional force that includes troops from Chad has retaken much of its territory in the last two years.

The group has largely focused its attacks on northeast Nigeria, neighboring Cameroon and Niger, with attacks in Chad less frequent.