Afkham also stressed Egyptians' national solidarity and unity to prohibit fight and plots in the country.
An al-Qaeda-inspired jihadist group claims it carried out the Friday deadly bombings that targeted Cairo police headquarters and a metro station.
"The explosion was against the oppressive and unfaithful security forces," the Ansar Beit al-Moqadas, a group based in the Sinai Peninsula, said on Twitter, Ahramonline reported.
A third bomb went off in the Egyptian capital Friday, hitting near a police station hours after a car bomb outside police headquarters killed four people an injured more than 50 civilians, an interior ministry official said.
The third explosion, near a police station in the west Cairo Talebiya district on the main road leading to the Giza pyramids, caused no fatalities, the police general said.
A second bomb had gone off near a metro station in the Dokki district, in the West of the capital city, killing one and wounding five police officers, a health ministry official said.