CAIRO, Aug 19: Militants killed 25 policemen in Egypt on Monday in the deadliest attack of its kind in years, as the army-installed rulers escalated a campaign to crush ousted president Mohamed Morsi’s Muslim Brotherhood.

The assailants fired rocket-propelled grenades at two buses carrying police in the Sinai Peninsula, security sources said, just hours after 37 Brotherhood prisoners died in police custody.

The bloodshed came after Egypt’s military chief vowed a “forceful” response to violence roiling the nation. Judicial sources said new accusations of inciting the death of protesters had been levelled against Morsi, who has been held in a secret location since the military deposed him on July 3.

The Sinai attack raised fears of a return to the wave of deadly violence that swept the country in the 1990s.

Egypt is struggling to put a lid on a deep political crisis and violence that has killed almost 900 people in days of clashes between Islamist protesters and security forces across the country.

Western states have condemned the violence and are threatening to cut off billions of dollars in aid, though Saudi Arabia said on Monday that Arab nations would step in to fill any gap. Morsi loyalists vowed new demonstrations, although a day earlier they had cancelled some marches citing security concerns.

The interior ministry said 25 policeman were killed and two injured in the Sinai attack, which it blamed on “armed terrorist groups”.

A border official said afterwards that the Rafah crossing with the Palestinian Gaza Strip, near where the attack occurred, would be closed.

The security situation in the Sinai has deteriorated sharply in the past weeks, with near daily attacks by militants targeting police and military installations.

Authorities said 37 Islamist detainees died after police fired tear gas in a bid to free an officer taken hostage by prisoners, as the inmates were being transferred to a Cairo jail. But the Brotherhood, the once-banned movement from which Morsi hailed, held the police accountable, accusing them of “murder”.

They said the incident affirmed “the intentional violence aimed at opponents of the coup, and the cold-blooded killing of which they are targets”.—AFP