Fifteen militants were killed in the Sinai Peninsula by rocket fire, Egyptian state TV reported on Tuesday, after witnesses said army helicopters had attacked militant strongholds in the area.
The state-run Nile TV gave no further details in a brief report. The army helicopters had targeted two villages south of Sheikh Zuweyid, a town near the border with Israel and the Hamas-run Gaza Strip.
An army source said a ground operation was under way with air cover, but declined to give further details because it was still continuing.
Earlier, and Egyptian security official said that helicopters rocketed militant hideouts in the northern Sinai Peninsula, killing and wounding dozens.
The official said the two helicopter gunships fired 13 rockets after surprising militant gatherings on Tuesday in two locations, al-Muqataa and Touma, south of the town of Sheikh Zuweyid near the border with Gaza.
He said "dozens" of militants were killed and wounded but that fighting was still ongoing. He did not mention if there were yet any soldiers on the ground to assess the number of casualties.
The official spoke on condition of anonymity according to rules.
Attacks by Islamic militants surged in the lawless Sinai after the toppling of Egypt's President Mohammed Morsi in a July 3 coup.
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