Six military police officers have been killed in an attack on a checkpoint on the outskirts of Cairo, Egyptian state media has reported.
Major General Mahmoud Yousri, the chief of security of Qalubiya province, told the state news agency MENA that the attackers stormed the checkpoint early on Saturday in the Shubra al-Kheima suburb.
Yousri said explosive disposal experts managed to defuse two bombs left behind by the attackers.
Follow our ongoing coverage of the political crisis in Egypt
It was the latest in a series of attacks on security forces across Egypt in recent months, and comes just two days after a soldier was shot dead as armed men attacked an army bus in the capital.
The army blamed both Saturday's and Thursday's attacks on the Muslim Brotherhood, which backed the ousted president, Mohamed Morsi.
The group did not immediately comment on the latest attack, but it has strongly condemned the previous one, saying the targeting of army soldiers and civilians is a "heinous crime that requires a thorough and transparent investigation to bring the perpetrators to justice".
Armed groups have launched scores of attacks, mainly targeting security forces, since the military overthrew Morsi in July. About 300 security officers have been killed.
Most of the attacks have taken place in the restive Sinai Peninsula, but in recent months the violence has also reached the Nile Delta and the capital.
The most prominent attacks, including a car bombing at a police headquarters in Cairo and the downing of a military helicopter in Sinai, have been claimed by Sinai-based Ansar Beit al-Maqdis.
The group has said the attacks are in retaliation for a brutal government crackdown on Morsi's supporters, which Amnesty International says has killed 1,400 people.