|The government has beefed up security in the north following a series of attacks blamed on Boko Haram [AFP]
A prison break by an armed group known as Boko Haram has raised fears of renewed violence in northern Nigeria just months before elections.
The group staged a raid on the prison on Tuesday night in the town of Bauchi, freeing more than 100 followers.
The attack left the prison in ruins and showed the group, which is seeking to institute sharia [Islamic law] in the country, had access to the sophisticated weapons it needed to overpower prison guards.
Nigeria's interior minister said on Wednesday the rebels had "overwhelming firepower" and guards were unable to stop them.
"Due to the overwhelming firepower which the attackers deployed on their mission, they were easily able to overcome the stiff resistance which was put up by the gallant prison officers who attempted to block the progress of the assault on the prison," Emmanuel Ihenacho, the minister, said.
The attackers, wielding AK-47 assault rifles, fired on the prison guards as they were breaking their daily Ramadan fast on Tuesday evening, Al Jazeera's Yvonne Ndege reported from Abuja, Nigeria's capital.
Between 800 and 900 of the prisoners broke out of the jail, including 200 inmates believed to be Boko Haram members, Ndege said. Four people were wounded in the clash.
Authorities have arrested 13 suspects in connection with the prison break, Ndege said, although residents in and around Bauchi remain afraid that Boko Haram will launch other attacks.
Danlami Yar'Adua, Bauchi's police commissioner, told the Reuters news agency that two of the dead were "bodyguards" and that the attackers had set part of the prison on fire.
One Bauchi resident told Reuters the attackers had numbered around 50. Police and military officers manned new checkpoints on the road out of Bauchi on Wednesday, hoping to catch escapees, the Associated Press reported.
Boko Haram - which means "Western education is sin" in the northern Hausa language - was blamed for riots and attacks in the north last summer that left more than 700 people dead.
Following the killing of several policemen by motorcycle-riding assailants over the past week, the government has tightened security in the north and northeast, and residents are fearful of a new wave of violence.
The Tuesday prison break coincided with the government's announcement that it would hold its presidential election on January 22.
Source: Al Jazeera and agencies