The bombings, all targeting the police, came as street clashes between Islamist supporters of deposed president Mohamed Morsi and backers of the military killed seven people, ahead of today’s planned rallies to mark the revolt that drove Hosni Mubarak from power.
In the first attack, an assailant rammed a bomb-laden car into a metal fence surrounding the Cairo security directorate at about 6:15am, killing four people and wounding more than 70, police officials and the health ministry said.
The blast, which badly damaged the facade of the building, left a large crater in the ground and sent a plume of smoke billowing above the city.
Interior ministry spokesman Hany Abdel Latif said “the vehicle tried to get close to the building but was stopped at the gate. Casualties were relatively small given the size of the blast”.
Friday is the Muslim day of prayer and rest, and so relatively few people were on the streets.
The bombing also damaged the nearby Museum of Islamic Art, bringing down ceilings and damaging exhibits, culture minister Mohamed Ibrahim told AFP.
State television said investigators had found the remains of the suspected suicide bomber. Hours later, a makeshift bomb exploded near a police vehicle close to a metro station in the neighbourhood of Dokki, killing a police conscript.
Two other bombs went off hours apart in a neighbourhood close to the Giza pyramids, one killing a person and wounding four conscripts near a cinema.
The other struck outside a police station, without causing any casualties.