Cairo, Egypt (CNN) -- Egypt's interim government has released the brother of Ayman al-Zawahiri, al Qaeda's second in command, his lawyer told CNN on Friday.
Mohamed al-Zawahiri was released Thursday along with scores of other political prisoners after orders from Egypt's Interior Ministry, said Nizar Ghorab, who claimed al-Zawahiri was tortured in prison.
Al-Zawahiri had been in jail since 1999 after being detained and extradited from the United Arab Emirates on allegations that he was linked to the assassination of former Egyptian President Anwar Sadat. Al-Zawahiri was acquitted on the assassination charges but later was accused of conspiring against the Egyptian government.
Human rights groups had long accused the regime of ousted President Hosni Mubarak of illegally detaining Islamists whom they deemed threats to the regime.
"His incarceration was based on injustice under the tyranny of Mubarak's rule, which left him stripped of his rights," Ghorab said. "He's never carried a weapon or taken part in any terrorist-related crimes."
Last week, the Interior Ministry ordered the release of two other men convicted of taking part in Sadat's assassination plot. The two members of the outlawed Islamic Jihad group had remained behind bars despite serving out their full sentences.