On the spot: shell hits Gaza market| Europe split over response | Troops face battle of tunnels | London protests

Israeli tanks and infantry battalions swept up to the very edges of Gaza City today, battling die-hard Hamas fighters and sealing off the bomb-scarred capital city from the rest of the coastal territory.

With the civilian death toll rising by the hour and diplomatic efforts to halt the fighting making no headway, the head of the UN refugee agency called the situation a “catastrophe”.

But Israel made clear it was not about to heed calls for a swift ceasefire to “Operation Cast Lead”. It insisted that it had to smash Hamas and destroy its weapons stockpile in order to ensure a lasting peace not just for its citizens, who have endured years of Palestinian rocket fire, but for the people of Gaza themselves.

Ehud Barak, the Defence Minister and architect of the assault on Gaza, said that the operation would be “expanded and intensified” as much necessary. “War is not a picnic,” he said.

Hamas fired more rockets into southern Israel today despite the Israeli army’s push to the very edges of Gaza City. With armoured columns pressing in from three different points on the northern end of the strip and from the centre, the territory was cut in half.

Israeli forces pushed all the way to the seashore just south of Gaza. They secured the hilly area where the Jewish settlement and Israeli army base of Netzarim once stood before the Gaza pullout ordered by Ariel Sharon, the former Israeli leader who suffered a debilitating stroke exactly three years ago.

With the north sealed off and heavy fighting under way between Israeli forces and Hamas guerrillas, more Israeli tanks moved into the southern area of the strip, cutting off Rafah, and its key smuggling tunnels under the Egyptian border.

The incursion stopped the trickle of aid trucks that had been making their way to Gaza’s hospitals, depleted of medicines and fuel for their emergency generators.

“We have a catastrophe unfolding in Gaza for the civilian population,” said John Ging, the head of the UN refugee agency in the Gaza Strip. “They’re in their houses, they’re not safe, they’re being killed and injured in very large numbers, and they have no end in sight.”

With fighting moving ever closer to Gaza City, many were simply fleeing their homes after tanks shells hit residential buildings in the cramped streets of the strip. But there was nowhere to go, with Israeli forces blocking the road south and trundling in from the north and east, and navy gunships lobbing shells from the Mediterranean.

In Gaza City an Israeli tank shell killed a family of five Palestinians, including a 14-year-old girl, when it hit their car.

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