Egyptian Armed Forces Spokesman Colonel Ahmed Ali said on Sunday that the army's "anti-terrorism" operation in North Sinai on Saturday resulted in 25 casualties among targeted militants, but gave no details on the exact numbers of those killed versus injured.

However, Reuters' Aswat Masriya website reported that at least 15 were killed in Saturday's offensive when army Apache helicopters targeted "terrorist sites" in the town of Al-Thoma south of Sheikh Zuweid. 

Ali said  that the military operation started at nine o'clock in the evening and asserted that "the army will continue to fight against militants in North Sinai." 

Meanwhile, the Egyptian army continued to fire on Sunday on what it describes as "terrorist sites" in North Sinai on Sunday as part of a recent military crackdown on Islamic militants in the restive peninsula.

The army bombed several four-wheel drive vehicles in the towns of Al-Thoma and Um Gamaan, also south of Sheikh Zuweid, claiming militants use them to attack security sites, Al-Ahram Arabic news website reports.

The army's Apache helicopters continued to hover over the area, the website added.

Eight were also arrested, suspected of involvement in militant activity.

Meanwhile, funerals proceeded for two people who were killed in the army's offensive in Sheikh Zuweid late on Saturday, eyewitnesses told Al-Ahram.

The army warned citizens over loudspeakers not to leave their homes to shield themselves from rocket fire from military helicopters, Aswat Masriya reported.

However, a number of small houses caught on fire as a result of the bombing, according to Al Ahram Arabic news website.

Residences' windows were damaged as a helicopter dropped a rocket in the area. 

Egypt's Sinai Peninsula has been experiencing security turmoil since president Mohamed Morsi was ousted on 3 July. Militants have repeatedly attacked police and military sites, killing dozens.   

Last week, the army announced it arrested 103 "terrorists", currently being interrogated, and that 60 were killed in its crackdown on terrorism during the period from 5 July to 4 August.