Al Qaeda's Iraq-based arm called on Egyptian Muslims to free all prisoners from their nation's jails, issuing an appeal for holy war as Cairo said Islamist militants had already escaped during anti-government turmoil.
The Islamic State of Iraq (ISI) attacked the Egyptian government for failing to implement strict Islamic law, and said it was better for Muslims to die fighting their government rather than live under its rule.
Egyptian Vice President Omar Suleiman said on Tuesday that militants linked to al Qaeda were among the thousands of prisoners who escaped from jails last month during the unrest triggered by a popular uprising.
The ISI's "War Ministry" called on Egyptians to free more prisoners. "Don't rest until you have rescued them all, then destroy them (the prisons) with the aid of God, so that not a single stone remains standing," it said in a statement which was posted on Islamist websites on Tuesday.
The ISI's links to Egyptian militants and the strength of its influence are unclear, but some analysts said the group may have inspired a deadly attack on an Egyptian church last month.
The Muslim Brotherhood, an Islamist organisation seen as Egypt's largest opposition group, renounced violence decades ago and has warned that government efforts to stamp out its influence could push some towards more radical ideas.
Calling for a holy war against Egypt's government, the ISI said: "If the people of Islam die trying to reach this goal, it is better for them than having a tyrant who rules them with laws other than God's Sharia law.
"Here is the market of jihad, and all the reasons to facilitate it in your home. The doors of martyrdom have opened."
Hundreds of thousands of Egyptian protesters of various political and religious backgrounds have taken to the streets over the past two weeks to demand President Hosni Mubarak end his three-decade rule.
ISI has been blamed for releasing statements to inspire church bombings after it attacked a Baghdad church last year.
Egyptian officials have said "foreign elements" orchestrated a suspected suicide bombing on a Coptic church in Alexandria on Jan. 1, killing 21 people, and linked the bomber to al Qaeda.