Egyptian security forces have identified seven people, including one Egyptian, suspected of involvement in the killing of 16 border guards in Rafah in the Sinai Peninsula on 5 August.

The attack, the worst since Egypt's 1973 war with Israel, triggered the biggest security operation in the region for decades, Interior Minister Ahmed Gamal El-Din said.

Lawlessness in Sinai has worsened since the overthrow of Hosni Mubarak in early 2011, and his successor, President Mohamed Morsi, has vowed to restore order.

"The security apparatus has succeeded in identifying the perpetrators of the incident that killed Egyptian soldiers in Rafah," Gamal El-Din told state-owned Al-Akhbar newspaper on Thursday.

He said the Egyptian suspect belonged to a dormant local jihadist cell but did not mention the nationalities of the other suspects, nor is it known if any of the suspects were detained.

Security forces are still trying to root out members of "disparate" militant groups, some of whom espouse the "takfiri" doctrine, which sees modern society as godless and therefore to be avoided, or attacked.

A complex relationship between hardline Islamist groups, security forces and local Bedouin tribes hostile to the Cairo government complicates efforts to pacify the region. It also makes it harder to verify reports of the security mission in the isolated region and the local response.

Joint army-police raids on suspected militant hideouts began a few days after the attack, employing attack helicopters, armoured vehicles and hundreds of troops.

The army says 11 militants have been killed and 23 arrested, 11 vehicles impounded and weapons seized including five boxes of Israeli-made ammunition.

The crackdown has the cautious approval of Israel which is alarmed by the increasing audacity of the Sinai militants. Analysts say some of them may have links to Al-Qaeda.