Cairo:
A blast rocked the Egyptian capital Cairo on Thursday, but officials could not immediately confirm if the explosion in front of a police building had caused any casualties.
The powerful explosion in a northern district of the city came in the middle of the night, an AFP journalist said, as Egyptian security forces are being targeted by Islamic State jihadists waging an Islamist insurgency.
"An attack targeted a state security building," a security official told AFP, speaking on condition of anonymity.
"The explosion partially destroyed the building," said a colleague.
No one has yet claimed responsibility for the blast, but Sinai Province, the Egyptian branch of the Islamic State group regularly carries out attacks on security services as part of an insurgency that has swelled since the army's ouster of president Mohamed Morsi in July 2013.