The African Union says it has authorized sending 5,000 peacekeepers to Burundi to stop deadly unrest there over President Pierre Nkurunziza's extended tenure in office from deteriorating further.

In a statement on Friday, the regional group's Peace and Security Council said an African Prevention and Protection Mission will be deployed to Burundi for at least six months. The mission can be extended.

Violence in Burundi has been escalating since Nkurunziza was re-elected in July for a third term. The move was opposed by many Burundians and the international community, which say it violates the country's constitution.

Eighty-seven people died last week when unidentified attackers struck at three military installations. At least 400 people have been killed since April 26, when the ruling party announced Nkurunziza's decision to run again.