Updated

The leader of the radical Islamic terrorist network Boko Haram has denied his group is taking part in any peace talks with Nigeria's government.

In a video given to local journalists in northeast Nigeria, Abubakar Shekau threatens the life of a man who in recent months claimed to be a Boko Haram leader and told the public the group was negotiating with the government. Shekau also said the group has had difficulties placing its messages online recently, requiring them to pass it onto messengers.

Shekau said: "Whoever kills any of our members should await a grave retaliation from us."

The Associated Press could not immediately confirm the authenticity of the video, though the man on the video looked like Shekau and sounded like his voice. The video carried no date.