Yemen sentenced on Saturday three Al-Qaeda militants to jail terms ranging from two years to six years.

The ruling against the militants Ahmed Moslih Al-Qahtani, Idris Ahmed Saleh and Abdullah Nasser Al-Maslami was delivered by the primary specialized penal court in the capita Sanaa.

They were convinced of forming a terrorist group which attacked military and security, public and foreign installations in the provinces of Abyan, Shabwa, Sanaa and Marib during 2009 and 2012.

Al-Qahtani was sentenced to six years, Saleh to four years and Al-Maslami to two years.

The court acquitted a fourth person.

Separately, eight prisoners were killed and three others injured, some seriously, after a fire broke out inside the central prison in Yemen's Ibb province on Saturday, the state-run 26 September website reported.

The website quoted a local security source as saying the prisoners, who died, had been convicted to murders and had suffered from mental illnesses.

The prison administration has formed a team to investigate the accident and the results will be announced through media after completing the probe, it said.