Officials said the prisoners were set free on Saturday and Sunday, and had all signed pledges to refrain from violence, although the security sources did not say when that happened.
Al Jazeera's sources expect Cairo to release a new batch of Islamic Jihad group members soon, after its prominent leaders Aboud and Tareq al-Zumor submitted what observers called an apology for violent operations carried out by the group.
Egypt has released hundreds of Jihad members since 2006 in a series of batches, a security source said.
Prior prisoner release

In November 2005, Egyptian authorities also released a group of 150 prisoners on similar conditions, most of them members of a separate Egyptian group, Al-Gamaa al-Islamiya.


The groups Islamic Jihad and al-Gamaa al-Islamiya lost a bloody 1992-1997 campaign to topple Hosni Mubarak, the Egyptian president. Earlier, in 1981, an Islamic Jihad fighter shot dead Anwar Sadat, the then-president of Egypt.


After Egyptian security forces crushed the movement, many members were jailed, and the group is not believed to have carried out any attacks since the mid-1990s.


Security sources were unable to say how many members from either group are still in prison.