Cairo, Egypt: A bomb blast killed six people, including three Egyptian policemen, as a team of officers on Thursday raided an apartment in Cairo suspected to be a militant hideout, the interior ministry said.
The explosion in the capital's Al-Haram district, near the pyramids, came ahead of next week's anniversary of the 2011 revolution that ousted longtime autocrat Hosni Mubarak.
The interior ministry blamed Thursday's incident on the blacklisted Islamist Muslim Brotherhood movement of ousted president Mohamed Morsi.
"Police had information that a group of Muslim Brotherhood members were preparing to carry out aggressive acts in the coming days using explosives and crude bombs," the ministry said on its Facebook page.
"This group was using an apartment in a Cairo building, and on Thursday night the police raided this apartment where they found a number of crude bombs.
"When the bomb squad expert were dealing with one of the bombs, it exploded killing three policemen, one civilian and two unidentified men."
Thirteen other people were wounded, the ministry said, after a police officer had put the number at 15.
Security officials said the impact of the explosion damaged part of the residential building housing the apartment.
Al-Haram has witnessed several attacks and gunfights since Morsi's overthrow in July 2013.
The neighbourhood is known to house many sympathisers of Morsi and it used to be a regular venue for clashes between his supporters and security forces in the aftermath of his ouster by then army chief and now President Abdel Fattah al-Sisi.
Warning against anniversary 'chaos'
It also houses several hotels used by tourists visiting Cairo because of its proximity to the pyramids.
Militants have regularly attacked policemen and soldiers since the army toppled Morsi.
The Cairo bomb blast comes after gunmen killed five policemen late Wednesday when they attacked a checkpoint in the North Sinai town of El-Arish.
The Islamic State jihadist group's Egyptian affiliate, the Sinai Province, claimed that attack.
The Sinai Province is spearheading an insurgency against security forces in the region, and has carried out deadly attacks in North Sinai as well as in other cities including Cairo.
Jihadists say their attacks are in retaliation for a brutal government crackdown targeting Morsi's supporters that has left hundreds dead and thousands imprisoned.
Morsi was Egypt's first freely elected president and succeeded Mubarak, who was driven from power after an 18-day popular uprising.
On Monday, Egypt marks the fifth anniversary of the anti-Mubarak revolt, and Sisi has warned against any form of demonstration on that day.
The Muslim Brotherhood has called for protests throughout January.
But its ability to mobilise supporters has diminished amid the blistering government crackdown that has seen several of its top leaders jailed and some sentenced to death and lengthy prison terms.
The interior ministry has warned against any "chaos" on Monday, and has boosted security across Egypt, including around the capital's iconic Tahrir Square -- epicentre of the anti-Mubarak revolt.