Egypt's State Security Prosecution has ordered the detention of a militant Islamist leader for 15 days over his alleged involvement in a bomb attack on Interior Minister Mohamed Ibrahim.
Nabil El-Maghraby, a former naval intelligence officer, was arrested on Sunday over his links to ex-army major Waleed Badr who allegedly blew himself up on 5 September in a failed attempt to kill Ibrahim, sources said.
El-Maghraby, an alleged Al-Qaeda operative, served 31 years in jail for taking part in the 1981 assassination of president Anwar Sadat, who was killed by Islamist soldiers opposed to his 1979 peace treaty with Israel.
He was released from jail in 2012 after Mohamed Morsi pardoned around 100 political prisoners, mostly Islamists.
A Sinai-based Islamist militant group called Ansar Bayt Al-Maqdis released a video of Badr urging Muslims to kill government officials in Egypt, a strategic US ally.
Al-Qaeda-linked Islamist militants based in the Sinai Peninsula have stepped up attacks on soldiers and police since the army deposed Morsi in July amid mass nationwide protests against his rule.
Most attacks have been carried out in the largely lawless Sinai Peninsula, but some attacks have taken place elsewhere, provoking fears of a countrywide Islamist insurgency.