Funerals were held in several provinces for those killed, whose coffins were wrapped in Egyptian flags.
At least 55 policemen were killed in the exchange of fire with the militants during a raid on a hideout near Cairo, Egypt.
Dozens of Egyptian police were killed in clashes with militants in the country's western desert on Friday, one of the deadliest attacks this year suffered by Egypt's security forces fighting a persistent and spreading Islamic militancy.
There has not yet been a claim of responsibility.
Police on their way to a hideout used by the Hasm militant group reportedly came under attack with rocket-propelled grenades.
The sources said authorities were following a lead to an apartment thought to house eight suspected members of Hasm, a group which has claimed several attacks around the capital targeting judges and policemen since previous year.
The public prosecutor has ordered the state security prosecution to start an investigation into the incident, an official said.
In total, 53 members of the security service died, sources told the BBC.
President Abdel Fattah al-Sisi was scheduled yesterday to attend events in the northern town of El Alamein on Egypt's Mediterranean coast to mark the 75th anniversary of the pivotal Allied World War II victory in the Battle of El Alamein.
The country has been in a heightened state of turmoil and violence since the military overthrew President Mohammed Morsi of the Muslim Brotherhood, the country's first democratically-elected president, in mid-2013 following mass protests against his rule. The Muslim Brotherhood has denied any involvement in violent attacks against security forces.
Hasm has claimed multiple attacks since 2016 on police, officials and judges in Cairo.
Egypt has been under a state of emergency since earlier in the year when IS militants launched a series of bombings and suicide attacks that killed scores of Coptic Christians.