Nigeria - President Jonathan Sacks Defence Chiefs

Nigerian President Goodluck Jonathan sacked his defence minister and national security adviser on Friday, but gave no reason for the move, after several months of violence by Islamist sect Boko Haram across the country.

"The president has relieved the NSA (national security adviser Owoye Azazi) of his job and replaced him with Colonel Sambo Dasuki," said presidency spokesman, Reuben Abati.

"The president has also sacked the minister of defence (Bello Mohammed) and will announce his replacement later."

Boko Haram, seen as the number one security threat in Africa's top energy producer, has killed hundreds in an insurgency against Jonathan's government this year.

A state of emergency and a military crackdown on the sect across the north have failed to quell the insurgency.

The northeast-based sect mostly targets security forces or authority figures but in the past year has turned its sites on Christian worshippers, attacking churches in an apparent attempt to stoke a wider sectarian conflict.

At least 92 people have been killed in violence between Muslims and Christians in the northern city of Kaduna in the past three days.

Jonathan drew criticism this week for travelling to Brazil for a climate change conference at the height of the religious violence in Kaduna.