Helicopters fired heavy machine guns to keep residents from open areas that have allegedly been used to launch rockets, witnesses said.

Early on Wednesday, more than 40 Israeli tanks and armoured vehicles invaded Sharq al-Idara al-Madaniya and Abd Raba farm, east of Jabaliya town, and demolished farmlands in the area close to the Green Line, east of the Gaza Strip.

The towns were sealed off, Aljazeera's correspondent reported.

Other vehicles tightly besieged Badawiya village, took up positions on the outskirts of the town of Bait Lahiya and seized control of Bait Hanun farm, al-Tarbiya and al-Ta'lim district, overlooking Shaikh Zayyid's city north of Bait Lahiya.

Medics said six Palestinians were wounded by Israeli fire.

A spokesman for the Israeli occupation army said the latest raid, one of the biggest in north Gaza in months, "was to stop and prevent the firing of more rockets at Israeli towns".

The raid came a day after Israel's strike against Hamas resistance fighters, killing 14 in Gaza City - the highest single-day toll in the coastal enclave since 12 May, when troops killed 15 Palestinians in raids in Gaza City and the southern Gaza Strip.