Egypt's interior minister on Thursday ordered extra security around opposition leaders Mohamed ElBaradei and Hamdeen Sabbahi after a religious edict calling for their deaths, a ministry spokesman said.
Mohammed Ibrahim issued the order to boost protection around the homes of leading dissident and former UN nuclear watchdog chief ElBaradei as well as former presidential candidate Sabbahi.
The move came after radical cleric Mahmud Shaaban issued a fatwa sanctioning the death of leaders from the opposition National Salvation Front, basing his arguments on Islamic law.
In a programme on a satellite television channel, he mentioned both ElBaradei and Sabbahi by name.
Another hardline cleric, Wagdi Ghoneim, also called on Muslims to "kill the thugs, criminals, and thieves who burn the country," state media reported.
The edicts were condemned by the government and by Al-Azhar, Sunni Islam's main seat of learning.
On Wednesday, ElBaradei had slammed the Islamist government of President Mohamed Morsi for failing to respond swiftly to the fatwa.
"Regime silent as another fatwa gives licence to kill opposition in the name of Islam. Religion yet again used and abused," he said in a twitter message.
On Thursday, Al-Azhar's Islamic Research Academy warned that such edicts could lead to "sedition and disturbance."
Prime Minister Hisham Qandil also condemned the fatwas and said the government would take legal action.
The order for security protection comes a day after Tunisian opposition leader Chokri Belaid was gunned down outside his home in Tunis, in what his family said was an assassination by Islamists.