(Ahlul Bayt News Agency) - The first bomb struck the Cairo security directorate around 6:15 am (0415 GMT), killing four people and wounding more than 70, the health ministry said.
Hours later, another bomb, a small makeshift device, was set off near a police vehicle close to a metro station, killing one person, according to the health ministry. That was followed by a third outside a police station on a road leading to the Giza pyramids.
The attacks came a day before police were to deploy across the capital for the third anniversary of the uprising against Mubarak, with Islamists calling for mass protests against the new regime.
A witness to the police headquarters bombing said the booby trapped car had stopped at the metal fence surrounding the building before the bomb went off.
"I was on the third floor, with the head of security," said the policeman, Mahmud Mushref, his head bandaged after he was injured in the blast.
"The car crashed into the fence, and the explosion happened," he said.
The blast left a large crater in the ground and sent a plume of smoke billowing above the city, an AFP correspondent reported.
"Casualties were relatively small given the size of the blast," said interior ministry spokesman Hany Abdel Latif.
The third small bomb was placed behind a billboard near a police station on the road leading to the Giza pyramids, the interior ministry said, adding it caused no casualties.
The facade of police headquarters and the front of the nearby Museum of Islamic Art were badly damaged by the earlier blast.
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