CAIRO, Egypt — About 135 Muslim extremists who spent more than a decade in Egyptian prisons have been released after signing statements renouncing violence, police said yesterday.

The prisoners all belonged to al-Jihad, a group once headed by Al Qaeda’s no. 2, Ayman Al-Zawahri. Egypt began releasing them two weeks ago, police officials said on condition of anonymity because they were not authorized to speak to the press.

Al-Jihad and the al-Gamaa al-Islamiyya group were both were accused of participating in the 1981 assassination of President Anwar al-Sadat. Al-Zawahri was jailed for his involvement in the assassination, but was released in 1984. He left Egypt and helped form Al Qaeda with Osama bin Laden in the late 1990s. Al-Gamaa first proposed a unilateral cease-fire in 1997 that went into effect in 1999. Most of its leaders, as well as hundreds of its members, have since been freed from prison.

Al-Jihad has long opposed reconsidering its radical views. But a few months ago, the group’s jailed top ideologue, Sayed Imam Abdul-Aziz el-Sherif, led a review of al-Jihad’s ideology and concluded it should renounce violence.