A Gaza War Full of Traps and Trickery

JERUSALEM — The grinding urban battle unfolding in the densely populated Gaza Strip is a war of new tactics, quick adaptation and lethal tricks.

Hamas, with training from Iran and Hezbollah, has used the last two years to turn Gaza into a deadly maze of tunnels, booby traps and sophisticated roadside bombs. Weapons are hidden in mosques, schoolyards and civilian houses, and the leadership’s war room is a bunker beneath Gaza’s largest hospital, Israeli intelligence officials say.

Unwilling to take Israel’s bait and come into the open, Hamas militants are fighting in civilian clothes; even the police have been ordered to take off their uniforms. The militants emerge from tunnels to shoot automatic weapons or antitank missiles, then disappear back inside, hoping to lure the Israeli soldiers with their fire.

In one apartment building in Zeitoun, in northern Gaza, Hamas set an inventive, deadly trap. According to an Israeli journalist embedded with Israeli troops, the militants placed a mannequin in a hallway off the building’s main entrance. They hoped to draw fire from Israeli soldiers who might, through the blur of night vision goggles and split-second decisions, mistake the figure for a fighter. The mannequin was rigged to explode and bring down the building.

In an interview, the reporter, Ron Ben-Yishai, a senior military correspondent for the newspaper Yediot Aharonot, said soldiers also found a pile of weapons with a grenade launcher on top. When they moved the launcher, “they saw a detonator light up, but somehow it didn’t go off.”

The Israeli Army has also come prepared for a battle both sides knew was inevitable. Every soldier, Israeli officials say, is outfitted with a ceramic vest and a helmet. Every unit has dogs trained to sniff out explosives and people hidden in tunnels, as well as combat engineers trained to defuse hidden bombs.

To avoid booby traps, the Israelis say, they enter buildings by breaking through side walls, rather than going in the front. Once inside, they move from room to room, battering holes in interior walls to avoid exposure to snipers and suicide bombers dressed as civilians, with explosive belts hidden beneath winter coats.

The Israelis say they are also using new weapons, like a small-diameter smart bomb, the GBU-39, which Israel bought last fall from Washington. The bomb, which is very accurate, has a small explosive, as little as 60 to 80 pounds, to minimize collateral damage in an urban area. But it can also penetrate the earth to hit bunkers or tunnels.

And the Israelis, too, are resorting to tricks.

Israeli intelligence officers are telephoning Gazans and, in good Arabic, pretending to be sympathetic Egyptians, Saudis, Jordanians or Libyans, Gazans say and Israel has confirmed. After expressing horror at the Israeli war and asking about the family, the callers ask about local conditions, whether the family supports Hamas and if there are fighters in the building or the neighborhood.

Karim Abu Shaban, 21, of Gaza City said he and his neighbors all had gotten such calls. His first caller had an Egyptian accent. “Oh, God help you, God be with you,” the caller began.

“It started very supportive,” Mr. Shaban said, then the questions started. The next call came in five minutes later. That caller had an Algerian accent and asked if he had reached Gaza. Mr. Shaban said he answered, “No, Tel Aviv,” and hung up.

Interviews last week with senior Israeli intelligence and military officers, both active and retired, as well as with military experts and residents of Gaza itself, made it clear that the battle, waged among civilians and between enemies who had long prepared for this fight, is now a slow, nasty business of asymmetrical urban warfare. Gaza’s civilians, who cannot flee because the borders are closed, are “the meat in the sandwich,” as one United Nations worker said, requesting anonymity.

It is also clear that both sides are evolving tactics to the new battlefield, then adjusting them quickly.

To that end, Israeli intelligence is detaining large numbers of young Gazan men to interrogate them for local knowledge and Hamas tactics. Last week, Israel captured a hand-drawn Hamas map in a house in Al Atatra, near Beit Lahiya, which showed planned defensive positions for the neighborhood, mine and booby trap placements, including a rigged gasoline station, and directions for snipers to shoot next to a mosque. Numerous tunnels were marked.

A new Israeli weapon, meanwhile, is tailored to the Hamas tactic of asking civilians to stand on the roofs of buildings so Israeli pilots will not bomb. The Israelis are countering with a missile designed, paradoxically, not to explode. They aim the missiles at empty areas of the roofs to frighten residents into leaving the buildings, a tactic called “a knock on the roof.”

But the most important strategic decision the Israelis have made so far, according to senior military officers and analysts, is to approach their incursion as a war, not a police operation.

Civilians are warned by leaflets, loudspeakers and telephone calls to evacuate battle areas. But troops are instructed to protect themselves first and civilians second.

Officers say that means Israeli infantry units are going in “heavy.” If they draw fire, they return it with heavy firepower. If they are told to reach an objective, they first call in artillery or airpower and use tank fire. Then they move, but only behind tanks and armored bulldozers, riding in armored personnel carriers, spending as little time in the open as possible.

As the commander of the army’s elite combat engineering unit, Yahalom, told the Israeli press on Wednesday: “We are very violent. We do not balk at any means to protect the lives of our soldiers.” His name cannot be published under censorship rules.

“Urban warfare is the most difficult battlefield, where Hamas and Islamic Jihad have a relative advantage, with local knowledge and prepared positions,” said Jonathan Fighel of Israel’s International Institute for Counterterrorism. “Hamas has a doctrine; this is not a gang of Rambos,” he said. “The Israeli military has to find the stitches to unpick, how to counterbalance and surprise.”

Israeli troops are moving slowly and, they hope, unpredictably, trying not to stay in one place for long to entice Hamas fighters “to come out and confront them,” Mr. Fighel said.

Today, he said, “the mind-set from top to bottom is fight and fight cruel; this is a war, not another pinpoint operation.”

Israeli officials say that they are obeying the rules of war and trying hard not to hurt noncombatants but that Hamas is using civilians as human shields in the expectation that Israel will try to avoid killing them.

Israeli press officers call the tactics of Hamas cynical, illegal and inhumane; even Israel’s critics agree that Hamas’s regular use of rockets to fire at civilians in Israel, and its use of civilians as shields in Gaza, are also violations of the rules of war. Israeli military men and analysts say that its urban guerrilla tactics, including the widespread use of civilian structures and tunnels, are deliberate and come from the Iranian Army’s tactical training and the lessons of the 2006 war between Israel and Iranian-backed Hezbollah in Lebanon.

Hamas rocket and weapons caches, including rocket launchers, have been discovered in and under mosques, schools and civilian homes, the army says. The Israeli intelligence chief, Yuval Diskin, in a report to the Israeli cabinet, said that the Gaza-based leadership of Hamas was in underground housing beneath the No. 2 building of Shifa Hospital, the largest in Gaza. That allegation cannot be confirmed.

While The New York Times and some other news organizations have local or Gaza-based Palestinian correspondents, any Israeli citizen or Israeli with dual citizenship has been banned for more than two years from entering Gaza, and any foreign correspondent who did not enter the territory before a six-month cease-fire with Hamas ended last month has not been allowed in.

Israel has also managed to block cellphone bandwidth, so very few amateur cellphone photographs are getting out of Gaza.

But Israeli tactics have caused civilian casualties that have created an international uproar, both in the Arab world and the West. In one widely reported episode, 43 people died when the Israelis shelled a street next to a United Nations school in northern Jabaliya where refugees were taking shelter. The United Nations says no militants were in the school.

The Israelis said they returned fire in response to mortar shells fired at Israeli troops. Such an action is legal, but there are questions about whether the force used was proportional under the laws of war, given the danger to noncombatants.

The backlash from the school attack is another potent example of the risks in an urban-war strategy: Israel may in fact be able to dismantle Hamas’s military structure even while losing the battle for world opinion and leaving Hamas politically still in charge of Gaza.

Taghreed El-Khodary contributed reporting from Gaza.