Bauchi, Nigeria - Inmates at a prison in northeastern Nigeria where members of a radical Islamic sect are incarcerated have torched part of the building a month after a jailbreak in which hundreds escaped, government officials said.
The jailbreak and a spate of recent killings of policemen and local officials in the northeast have raised fears that the sect, which staged an uprising in which hundreds died last year, is attempting a comeback.
Armed police and firefighters were sent in to control the unrest at the prison in the city of Bauchi, where heavily armed gunmen believed to be members of the Boko Haram sect freed close to 800 inmates in early September.
The sect, which wants sharia (Islamic law) applied more widely in Africa's most populous nation, attacked symbols of authority including prisons and schools in last year's uprising in Maiduguri, some 400 km (250 miles) northeast of Bauchi.
Bauchi state government officials said the riot at the prison, which holds Boko Haram members arrested during last year's trouble, was triggered by a dispute over an amnesty granted to some inmates, including two sect members.
"It was a protest by some of the prisoners who heard that the governor had granted amnesty to a few of them," Abdulmuminu Mohammed Kundak, an adviser to the state governor, said on Friday. "They should know that it is not every prisoner that will be released at the same time."
Boko Haram members said in a radio interview broadcast in the local Hausa language in Maiduguri last month that they were behind recent shootings and warned they would kill more police, traditional rulers and politicians.
Gunmen killed a vice chairman of the opposition All Nigeria People's Party (ANPP) at his home in Maiduguri, months ahead of nationwide elections, police said on Thursday. Local residents said they believed Boko Haram was responsible.
Nigeria was shaken by car bomb attacks in the capital Abuja a week ago, claimed by a rebel group in the oil-producing Niger Delta, hundreds of kilometres to the south.
It can ill afford insecurity in the north as it prepares for a vote set to be the most fiercely contested since the end of military rule just over a decade ago.
Security has been tightened in recent months in Maiduguri, with the police and army carrying out joint patrols and a dusk-to-dawn ban on motorcycles, used in some shootings.
Nigeria, a vast nation of more than 140 million people, is roughly equally divided between Christians and Muslims.
Boko Haram's views are not espoused by the vast majority of Nigeria's Muslim population, the largest in sub-Saharan Africa, although poverty, unemployment and a lack of education means sect leaders have been able to gain a cult-like following.