Abdel Hamid Musa Abu Aqrab, who headed the military wing of Al-Gama'a Al-Islamiya group, was convicted in June for the premeditated murder of two generals and two policemen who were shot dead in two attacks in 1992 and 1993.

Judge Abdullah Abu Hashem of the state security court commuted Abu Aqrab's sentence to 50 years in prison, or 25 years for each attack, citing the militant's failing health.

"The court has taken into account your health circumstances and has shown you compassion, sentencing you to life in prison," the judge said.

Egyptian authorities put down an Islamist uprising in the 1990s. Al-Gama'a Al-Islamiya, one of the militant groups to which Abu Aqrab belonged, targeted ministers, the police and tourists.

Abu Aqrab, who was active in Asyut in southern Egypt, said he was innocent. His group was also blamed for a failed 1995 assassination attempt on President Hosni Mubarak in Addis Ababa.

He had been tried in absentia for 15 years but gave himself up in 2007 and requested a retrial.

There are no signs of any return to an insurgency on the scale of the 1990s, but analysts say militants with no security records could carry out small and random acts of violence.

Egypt's emergency law has been in force almost continuously since Islamic militants assassinated President Anwar Sadat in 1981. Rights groups say it is used to secure swift and often overly harsh verdicts.