Gunmen stormed a prison in Kogi state in central Nigeria, killing one warden and freeing 119 prisoners, the prison authorities said on Thursday.

The invaders came at about 7.15 pm (1815 GMT) yesterday and we suspected they used explosives to bring down the gate of the prison and the roof of the gate and thereafter set free 119 inmates, said prison authorities spokesman Hadiza Aminu.

Islamist sect Boko Haram, which has killed hundreds in bomb and gun attacks this year, was behind a prison break in northern Bauchi state in 2010 when about 700 prisoners were freed.

Aminu said there were no Boko Haram members being held in the prison in Koton Karfi, which is about 100 kilometres (62 miles) south of the capital Abuja.

Boko Haram, which wants sharia law more widely applied across Africa's most populous nation, has become increasingly sophisticated and deadly in its methods in the last six months.

Although the majority of its attacks occur in its home base in the northeast, its threat has spread. At least 178 people were killed in the sect's most deadly attack last month in Nigeria's largest northern city Kano.

President Goodluck Jonathan has said Boko Haram have infiltrated the government and security services and have links with jihadist groups outside Nigeria, including al Qaeda's north African wing.

(Reporting by Camillus Eboh; Writing by Joe Brock; Editing by Louise Ireland)