Egypt has launched air raids on suspected Islamic militants in the Sinai Peninsula in the wake of the bloodiest ever militant attacks on the army.
The use of assault helicopters marked a sharp escalation in Egypt's fight against Islamic militants who have become increasingly active in the mountainous, desert peninsula bordering Israel. Earlier this week, militants stunned the Egyptian army with a surprise attack in which gunmen killed 16 soldiers, stole armoured vehicles and drove into Israel to attempt another attack.
In a statement read out on state TV, the military said it has started a joint military-police ground operation in Sinai, backed by warplanes, to "restore stability and regain control" of the Sinai. It provided little detail.
The Sunday ambush was one of the bloodiest attacks in Sinai in years and the deadliest against Egyptian troops, underlining the growing lawlessness of the territory, where security forces repeatedly have been targeted by militants, some loosely linked with al Qaida.
In the latest violence, gunmen opened fire on three security checkpoints around el-Arish, the capital of North Sinai province, 30 miles from the borders with Gaza and Israel. One of the attacks was on the checkpoint on the main road between el-Arish and the town of Rafah on the Israeli border.
The shootings wounded six people, among them a military officer, two soldiers, two policemen and a civilian whose condition is critical.
Helicopters carried out strikes using missiles in retaliation later, security officials said. They did not give further detail.
It was the first time the army has fired missiles in Sinai since Egypt's 1973 war with Israel, in which Egypt tried to recapture the then-Israeli held peninsula. Sinai reverted to Egyptian control under Cairo's 1979 peace treaty with Egypt. Israeli forces completed the withdrawal from the peninsula in 1982.
Sinai has seen lawlessness and militant violence in the past, but it became worse after the uprising that toppled Hosni Mubarak in February 2011. Amid the uprising, police and internal security forces all but disappeared from the streets across the country. In Sinai, militants have grown steadily bolder.
Residents say the militants far better armed than the security forces on the ground, which have repeatedly come under attack by militants. Since Mubarak's ouster, some of the groups have distributed fliers in Sinai urging the forces to leave the peninsula because, they say, it will be declared an Islamic state.