At the first sign of movement in the dark Gaza alleyway, Alon opened fire without hesitation. Snipers liked to operate at night, he said, and the area had been cleared of Israeli troops.

“He could have been advancing to attack,” the Israeli lieutenant explained. “We are treating everything as hostile right now. We were told not to take chances — to shoot rather than ask questions.”

Alon — he would only give his first name and rank — was part of the forces that took control of the Jabalya refugee camp in northern Gaza. It was his first day of recuperative leave out of Gaza since Israel began its ground offensive 12 days ago.

As Israel laid the groundwork for what is expected to be the third stage in its offensive, sending a stream of reservists in to support weary combat units, those soldiers on a break from the combat gave first-hand accounts of Israel’s military tactics.

“I’m not a newcomer in the army,” Alon told The Times. “Both my brothers served in combat units that saw action in Gaza. And I can say that this is the most aggressive line that we have ever taken towards fighting the Palestinians. As you say in English, the gloves were off.”

He was shocked by some of the scenes inside Gaza, describing whole neighbourhoods levelled. “It doesn’t look like we’ve been there a few weeks — it looks destroyed, demolished, like we were bombing it for years. You can’t imagine what damage we have done. We didn’t want any civilians to die, we do everything we can to make sure that Palestinian civilians there, the non-fighters, aren’t hurt. We tell them to leave the areas that we are fighting . . . but it’s not easy; what we are doing there is difficult work.”

Palestinian doctors say that more than 900 people have been killed, nearly half of them civilians, since Israel began Operation Cast Lead in Gaza on December 27. Thirteen Israelis have died, three of them civilians.

As speculation mounted over how long Israel would continue its punishing offensive, its soldiers appeared eager to take the fight to Gaza’s densely populated towns.

The troops said they had had a taste of the traps and tricks that Hamas had laid in store for them: booby-trapped houses, tunnels intended to spirit away kidnapped soldiers, militants dressed in civilian clothing — but insisted that the operation could not claim success unless Hamas was dealt a “knockout blow” by troops combing through the urban centres.

“It will expose us to more of their traps but it must be done. We have been learning, slowly circling them and moving closer in. We have them trapped now so we can’t stop.” Reporters embedded with Israeli forces in Gaza have described them as “moving slowly but shooting readily”.

In one account, tank crews leading an armoured column to the beachfront suddenly saw a person standing in an open cabana less than a mile away. The figure quickly retreated as the tanks opened fire. “There have been several attempts to use antiarmour weaponry against us, in at least one case a long-range missile,” said Lieutenant-Colonel Erez, a tank commander, giving only his first name as per standard military policy. “We have responded pre-emptively and forcefully. We also hit anyone seen trying to observe our movements.”

Lieutenant-Colonel Yehuda, whose men are situated in houses on the outskirts of Gaza City, said that it was standard practice for Israeli troops to enter suspicious buildings with bursts of shooting, to stave off a doorway attack. “In one case the building started burning but we managed to clear out our men in time,” he said.

His unit had not seen as much action as Alon’s but had fought off several attacks nonetheless, killing three gunmen who emerged from a bunker and a suspected suicide bomber who approached on a bicycle.

In another account, published in the Israeli media, the Armoured 401st Brigade convoy had left Gaza’s coast and was heading towards Israel when its commander spotted people, apparently armed, on a rooftop about 800 metres away from the road. A few days before the Israelis had dropped leaflets calling on all residents living near the road to get out.

Like Alon, Lieutenant-Colonel Yigal had little room for doubt. After checking none of his comrades were in the area — four Israeli soldiers were killed by “friendly” fire in the first days of the offensive — he gave the order and machineguns and tanks opened up.

For Alon, a return to the action cannot come fast enough. “It feels good to be winning again, to show that we are still the strongest army in the world,” he said — a reference to the 2006 Lebanon war, when confidence in the country’s forces was badly shaken by its inability to stop Hezbollah’s rocket attacks. “It was important to go in and remind them what we can do. It’s the only way to get them to stop.”

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