At least four have been injured in an explosion near the Sharqiya Governorate's Military Intelligence Headquarters in the city of Anshas midday Sunday, according to state TV.
The blast is believed to have been caused by a car laden with explosives detonating near the intelligence building, Director of Sharqiya's Criminal Investigations Office Atef Khedr told Al-Ahram's Arabic news website.
Army Spokesman Ahmed Ali confirmed on his official Facebook page Sunday that four soldiers had been injured by the blast which partially destroyed the building's rear façade. He condemned the terrorist attacks targeting Egypt's military and state facilities.
A security official told state news agency MENA Egyptian security forces have arrested a suspect in the explosion.
Egypt witnessed two explosions last week. On Tuesday, a huge bomb rocked the Security Directorate building in the Nile Delta city of Mansoura, killing 16 people and injuring more than 135, while on Thursday a smaller explosion near a public bus in eastern Cairo's Nasr City injured five people.
Ansar Bait Al-Maqdis, an Al-Qaeda-inspired Sinai-based militant group, claimed responsibility for the Mansoura bombing, yet Egypt's interim government blames the Muslim Brotherhood for the attack. The Brotherhood denies any involvement with the explosion.
No group has yet claimed responsibility for the Cairo bomb which, according to explosives experts, was planted on the road rather than on the bus, or Sunday's Sharqiya explosion.
The explosives experts have also managed to defuse another bomb found near the Nasr City explosion site, which reportedly targeted security forces expected to rush to the scene following the blast.
The explosions have sparked nationwide panic. On Saturday, the discovery of a dummy bomb in Alexandria University caused panic on campus among students and professors.
Experts who examined the bomb found it to be devoid of explosive material.
Militant attacks have spiked since the July ouster of Islamist president Mohamed Morsi. While initially centred in Egypt's restive Sinai Peninsula, the attacks have recently extended to additional governorates, with the Mansoura blast marking the largest to strike near the capital.