At least 700 prisoners have escaped during an attack on a jail in northern Nigeria, including members of a militant Islamist sect.
Police said four people died in gunfire after members of the Boko Haram group attacked the jail, breaking locks and setting parts on fire.
Officials said 150 suspected members of Boko Haram were among the escapees.
On Tuesday, authorities in the city of Maiduguri blamed the group for a series of recent killings over the past month.
Police commissioner Danlami Yar-Adua told AFP news agency that 732 inmates had escaped during the sunset raid, while 30 were left.
One soldier, one police officer and two residents were killed in the resulting shootout between attackers and security forces, while six others are in a critical condition.
"They came in large numbers, heavily armed, and began shooting at the prison gate," Salisu Mohammed, a guard, told AFP.
"Some of us were hit while others fled".
Supporters of the sect are now believed to be hiding in the surrounding mountains, police said.
BBC News
