Two mausoleums in North and central Sinai were bombed by unknown assailants late on Sunday, state news agency MENA reported, as militant attacks continue to rock the lawless Sinai Peninsula.
Bombs detonated at the sites of two separate shrines, one in the village of Rawda on the international freeway in northern Sinai and the second in Al-Hasna district in the center of the Peninsula, wrecking the domes and walls of both buildings, MENA added.
No deaths or injuries have been reported.
In May 2011, the Sheikh Zuwaid shrine in the northern Sinai town of Sheikh Zuwaid was blown-up in the same manner.
Since the popularly-backed army ouster of Islamist president Mohamed Morsi on 3 July, hard-line Islamist militants have stepped up their attacks on security forces near Egypt's border with Israel and the Palestinian Gaza strip.
At least 30 security personnel and civilians have been killed since early July. The army says they have killed dozens of alleged jihadists in its recent crackdown against militancy in the peninsula.
Hard-line salafists and jihadists, who believe that the erection of mausoleums for the dead constitutes blasphemy in the Islamic faith, have blown up a number of shrines across Egypt since the outbreak of the January 25 revolution.