Col. Tamer Rifa, an army spokesman, said in a statement on Sunday that at least ten militants were also killed and 245 others detained during anti-terror raids in the North Sinai city of Arish.
The spokesman added that warplanes attacked six militant targets in northern and central Sinai and the Nile Delta.
The deaths raise military casualties to at least 16 dead, along with more than 100 militants, since the start of the operation on February 9,
The army launched the campaign after Egyptian President Abdel Fattah el-Sisi gave them a three-month deadline to crush the Takfiri Daesh terrorists in Sinai.
Sisi issued the ultimatum in November after suspected Daesh gunmen massacred hundreds of worshippers in a Sinai mosque associated with Muslim Sufi mystics.
In recent years, militant groups have killed hundreds of soldiers, policemen and civilians in Sinai and elsewhere in Egypt.
Sinai has been the hotbed of militancy in Egypt since a coup led by Sisi ousted former President Mohamed Morsi in the summer of 2013. Sisi came to power a year later only to see attacks that had normally targeted security forces in Sinai expanded to the mainland Egypt to affect civilians.
A branch of Daesh, a Takfiri terrorist group that is on its last legs in Iraq and Syria, where it was most active, has been behind many attacks in Sinai and elsewhere. The group was blamed for the attack at a northern Sinai mosque in November that killed over 300 worshippers.
Many blame Sisi’s tough crackdown on dissent for the protracted violence in Egypt. Under the former army chief, the Egyptian judiciary has jailed tens of thousands of activists, many of them members or sympathizers of the outlawed Muslim Brotherhood, a political party from which Morsi and members of his cabinet had hailed.