A huge explosion at a security building in northern Egypt has killed at least 14 people and injured more than 100, officials and state media say.
The blast, reportedly caused by a car bomb, led to the partial collapse of the building in the city of Mansoura.
Interim Prime Minister Hazem Beblawi called it “an act of terrorism”.
Attacks on Egypt’s security forces and police have increased since the army removed Islamist President Mohammed Morsi in July.
No group has so far claimed responsibility for Tuesday’s blast.
Mr Beblawi told satellite channel ONTV: “The state will do its utmost to pursue the criminals who executed, planned and supported that attack.”
The Muslim Brotherhood – which supports Mr Morsi and has been banned by the interim authorities -condemned the bombing.
“Muslim Brotherhood considers this act as a direct attack on the unity of the Egyptian people,” it said in a statement.
Security chief ‘injured’
The explosion shook the building at about 01:10(23:10 GMT on Monday).
More than 100 people were injured in Mansoura, the capital of Dakahliya province in the Nile Delta region.
Media reports say the provincial security chief was among those wounded.
The blast shattered windows of nearby buildings and its impact was felt about 20km (12 miles) away, the reports say.
Since the removal of Mr Morsi – Egypt’s first democratically elected president – his supporters have been staging mass rallies demanding his immediate release.
More than 2,000 Muslim Brotherhood members have been arrested, and 450 of them on Monday went on hunger strike in protest at their “inhumane
Mr Morsi is now facing three separate criminal trials relating to his time in office. The first trial opened on 4th November but has been adjourned until 8 January.