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STORY: Israeli reserve forces gathered near the Gaza border on Friday (July 18), as Israel stepped up its ground offensive, pounding targets with artillery and using tanks and infantry to battle Hamas fighters.

To back up regular forces, Israel said it was calling up 18,000 military reservists, adding to 30,000 already mobilised.

Israel is preparing to step up its Gaza offensive, Prime Minister Benjamin Netanyahu said on Friday after ground troops were sent into the Palestinian enclave.

Orange flashes from Israeli navy gunboats' tracer rounds and helicopter air strikes rippled across the coastal enclave. Hamas launched mortars bombs at the invading troops and rockets across the border at the southern Israeli towns of Ashdod and Ashkelon.

Israel said one one of its soldiers was killed and several others wounded in Gaza clashes overnight. Hamas said its men were shelling the tanks with mortars and setting off bombs against