Nigeria's president has appointed a new army chief, the ministry of defence said in a statement on Thursday, following the death of the military head's predecessor in a plane crash last week.

President Muhammadu Buhari appointed Major General Farouk Yahaya who previously commanded troops operating in the northeast where security forces are fighting an Islamist insurgency, the statement said.

Nigeria's army faces several challenges including the insurgency waged by Boko Haram and its offshoot, Islamic State West Africa Province, that has displaced about 2 million people and killed more than 30,000 since 2009. Troops are also fighting armed gangs in the northwest who kidnap for ransom.

"Prior to his appointment Major General Yahaya was the general officer commanding 1 Division of the Nigerian Army and the incumbent theatre commander of the Counter terrorism Counter insurgency military outfit in the northeast," the statement said.

Yahaya's predecessor, Lieutenant General Ibrahim Attahiru, died in a plane crash on Friday on an official visit to the northern state of Kaduna. read more

Attahiru was appointed in January, alongside other military chiefs, after years of mounting criticism over spreading violence by Islamist insurgents and armed gangs.