Armed militants killed at least 52 policemen and conscripts in a gunbattle during a raid on a suspected terrorist hideout in Egypt's Western desert, security sources said on Friday.
An interior ministry statement confirmed the incident and said some of the attackers had died, without giving any figures for casualties or further details. It added that security forces are combing the area.
The security sources said authorities were following a lead to a hideout deep in the desert thought to house eight suspected members of Hasm, a group which has claimed several attacks around the capital targeting judges and police since last year.
A convoy of four SUVs and one interior ministry vehicle was ambushed from higher ground by militants firing rocket-propelled grenades and detonating explosive devices, a senior source in the Giza Security Office said.
The number of dead was expected to rise, security sources said.
The sources said six security personnel were injured in the clashes, while another source said that four of the injured were police and four others suspected militants.
The insurgency in the Sinai peninsula has grown since the ouster of president Mohammed Morsi in mid-2013 following mass protests against his rule.