Dozens of policemen were reportedly killed during a raid Friday on a militant hideout in the al-Wahat al-Bahriya area in the Giza province, about 135 kilometers (84 miles) from Cairo, Anadolu Agency reported.
An Interior Ministry statement confirmed the attack, but did not give casualty figures. It said a number of militants were killed in the shootout.
No group has yet claimed involvement in the attack.
State television said Saturday a security alert was declared in the al-Wahat al-Bahriya area on Egypt’s Western Desert to hunt down militants.
It said security sweeps would continue deep into the desert.
Details of Friday’s deadly shootout remain unclear. The Interior Ministry said the shootout took place during a raid to arrest a number of suspected militants in the area.
Security sources said the forces were ambushed during the raid.
Local media and unnamed security sources put the death toll of security forces at around 60. Egyptian authorities did not yet give any official death toll.
Egypt has been battling an insurgency since 2013 when the military deposed Mohamed Mursi, Egypt’s first freely elected president, in a coup.
The insurgency has been concentrated in the northern Sinai Peninsula, but attacks have spread in the mainland, including the capital.
Egypt has been under a state of emergency since April when a twin church attack killed scores.