Abu Duaa al-Ansari was killed with at least 45 other jihadis in an operation involving Egypt’s air force and anti-terrorism squad, according to army

An Egyptian airstrike has killed the head of the Islamic State affiliate behind scores of deadly attacks on security forces and the suspected of downing a Russian airliner, the army has said.

A posting on the Facebook page of the Egyptian military’s chief spokesman, Brigadier General Mohammed Samir, said Abu Duaa al-Ansari was killed in an operation south of the Egyptian coastal city of el-Arish.

Several senior aides and at least 45 other militants were killed in an operation carried out jointly by the air force and the anti-terrorism squad, according to Samir’s statement.

Since Egypt’s military overthrew the country’s Islamist president, Mohamed Morsi, in 2013, jihadis have led an insurgency against the army and police involving daily attacks in north Sinai.

Most of the attacks, which have killed hundreds of policemen and soldiers, have been claimed by “Sinai Province”, the Egyptian branch of Isis. A military source said that Ansari was the group’s “number one” leader.

The name of Abu Duaa al-Ansari is not widely known and had not been previously mentioned as that of the leader of the Sunni militant group, which was known as Ansar Bayt al-Maqdis, or Soldiers of Jerusalem, before it swore allegiance to the Isis group fighting in Syria and Iraq.

The army’s statement said dozens of others were “targeted with precise hits” in the operation against the group’s strongholds in the south and south-west of the Sinai city of el-Arish. The operation destroyed depots where weapons, ammunition and explosives were stashed, it added.

The military has poured troops and armour into the peninsula where security forces have been battling a jihadi insurgency since the former army chief who became Egypt’s president, Abdel Fattah al-Sisi, ousted Morsi more than three years ago. But the jihadis have remained defiant and kept up attacks mostly against the security forces using roadside bombs and ambushes. They have also targeted Egyptian Christians and have claimed attacks on foreigners and diplomatic missions, including last year’s attack on the Italian consulate in Cairo

In 2015 they the group also claimed to have beheaded Tomislav Salopek, a Croatian man who worked for French geoscience company CGG, after abducting him on a road running from the west of Cairo.

The group also claimed responsibility for bombing a Russian airliner carrying holidaymakers from an Egyptian resort last year, killing all 224 people on board. The group said it had smuggled a bomb on board at an airport in the south of the peninsula.

The army has regularly announced the death or capture of jihadis, who have often claimed their attacks were in retaliation for a police crackdown that has killed hundreds and left thousands in jail since Morsi’s removal from power.

The arid and rugged Sinai peninsula borders Israel and the Palestinian Gaza Strip. El-Arish is the provincial capital of North Sinai where the jihadis are active.