by Zhang Yanyang

    JERUSALEM, Jan. 13 (Xinhua) -- As Operation Cast Lead intensifies in its focus to uproot Hamas, the Israel Defense Forces(IDF) have been confronted with a whole new line of war tactics, Israeli army sources said.

    Boosted by two years of training from Iran and Hezbollah, the IDF said, Hamas changed the entire desert strip into a deadly web of booby traps and roadside bombs, and has utilized civilian houses, schools, mosques and medical facilities as weapon reservoirs.

    According to Israeli intelligence officials, an intricate network of tunnels below the Philadelphi Route along the Egypt-Gaza border has facilitated the flow of arms into the Gaza Strip and its destruction is one of the main goals of the IDF operation.

    But the tunnels underneath the Rafah crossing are not the only underground facilities Hamas uses.

    "There are two types of tunnels. The first type is on the border with Egypt and is used for smuggling. The other type is underneath the houses and is used for both storing weapons as well as to shelter terrorists on the run," IDF spokeswoman Major Avital Leibovitz told Xinhua.

    She noted that Hamas' strategy is to use a civilian shield to deter the Israeli response and benefit from international pressure on Israel for any civilian casualties.

    "Hamas tries to booby-trap most of the civilian areas, including houses, schools, and other civilian facilities," Leibovitz said. "I have a map in the office that was created by Hamas, which shows a booby trap in the middle of a civilian area, right by a gas station."

    Lieutenant Colonel Yehuda, a battalion commander in the Givati infantry regiment, noted that many of the houses his troops came across in Gaza were booby-trapped.

    "We came across several houses that were booby-trapped, either with regular explosives, or by sealing the windows and doors and leaving the cooking gas on," Yehuda said.

    "The idea was that when the IDF arrived, its standard procedure is to fire at anything suspicious in the building, and this would set off the gas. In one case the building started burning but we managed to clear out our men in time," Yehuda said.

    Leibovitz noted that Hamas also used remote control explosives to strike approaching troops.

    "They are using mannequins with explosives to draw the forces into the houses, and then operate their explosion by cellular. And they use interactive explosive devices planted on the windows and also operated by cellular to explode when a vehicle approaches," she said.

    She added that suicide bombers and mortars, the group's more traditional form of warfare, were still commonly used against Israeli soldiers.

    "Right now Hamas is under strong pressure and they're hiding in civilian areas, but they have hundreds of tons of explosives," Leibovitz said. "From the first day of the conflict they fired 670explosives."

    In order to cope with Hamas' new tactics, the Israeli army said it had equipped every soldier with a ceramic vest and helmet, and provided each unit with dogs to sniff out explosives and militants hiding in tunnels. To avoid booby traps and limit exposure to snipers and suicide bombers, Israeli troops generally entered and moved around buildings by breaking through the walls.

    The Israeli air force also found a way to circumvent Hamas' use of civilian shields, who were forced to stand on the roofs of buildings to deter the airstrikes. The Israeli warplanes drop missiles designed not to explode at empty areas on the roof to frighten off residents.

    Though Israel has adopted new tactics in response to the ongoing battle and changing conditions, analysts believe the most important strategic decision the Jewish state has made is to define its movement into Gaza as a serious war against an enemy entity rather than a tactical maneuver.

    Civilians in the battlefield are warned by fliers, loudspeakers and telephone calls to evacuate areas of combat, but troops are instructed to protect themselves first and civilians second.

    More than 971 Palestinians, half of whom were civilians, have been killed in the Israeli offensive since Dec. 27.

    As Hamas has sought shelter within the civilian population, the Israeli forces would not stand a chance unless they pursued a heavier approach, meaning that troops are covered by airpower, tanks and armored bulldozers and respond with heavy firepower to any apparent threat.

    "We came in very strong. Our doctrine is to take over our assigned positions, purging any resistance, and then fanning out as required, repeating the process." Yehuda said.

    "There have been several attempts to use anti-armor weaponry against us, in at least one case a long-range missile. We have responded preemptively and forcefully. We also hit anyone seen trying to observe our movements," said Lieutenant Colonel Erez, a tank commander.

    Israeli tactics have triggered international criticism, and the international community raised questions about whether the force it used was proportional given the danger to non-combatants.

    Though Israel's "heavy" strategy has proven successful in eradicating much of Hamas' combative ability, it is faced with an uphill struggle diplomatically.

    However, before the U.S. President-elect Barack Obama takes office on Jan. 20, and a new government is chosen in Israel on Feb.10, analysts believe Operation Cast Lead is more likely to intensify, as it might be Israel's last chance to deal with Hamas.