Three soldiers were killed in the first two days of the IDF’s ground campaign against Hamas in the Gaza Strip.On the 12th day of Operation Protective Edge on Saturday, two soldiers were killed and two were wounded in a firefight with a Hamas squad that infiltrated Israel in the Eshkol region via a tunnel from the central Gaza Strip on Saturday morning.The squad of nine terrorists was headed toward an Israeli community when it encountered an IDF patrol, a senior military source said.An exchange of fire ensued and one Gazan was shot dead, while a senior officer was wounded. The other terrorists fled back into the Strip through the tunnel.The terrorists were dressed in IDF uniforms and were armed with automatic weapons, rocket-propelled grenades, syringes, sedatives and handcuffs – the latter apparently to be used in taking hostages.The air force carried out a strike on members of the cell in Gaza, apparently killing several of its members.The soldiers killed by a rocket-propelled grenade while thwarting the attempt to murder Israeli civilians were Sgt. Adar Barsano, 20, of Nahariya, and Maj. Amotz Greenberg, 45, of Hod Hasharon, the army said.“Unfortunately, we are in a reality where this can happen,” the IDF source said.The IDF suffered its first casualties in Operation Protective Edge on Friday afternoon, as it began its ground offensive into Gaza. Twentyyear- old St.-Sgt. Eitan Barak from Herzliya was killed in Gaza, under still unclear circumstances. The IDF is investigating the incident to determine whether the Nahal Brigade fighter was hit by “friendly fire” or by terrorists.Barak was promoted posthumously on Friday. Two more soldiers were lightly wounded in the incident.Thus far during the ground incursion of Operation Protective Edge two IDF officers have been seriously wounded, three officers and a soldier were moderately wounded, and an officer and five soldiers have been lightly wounded in clashes with gunmen in Gaza.Large ground forces from the Paratroopers, Nahal and Givati infantry brigades are operating with the Armored Corps, the Engineering Corps, the Maglan special unit that works behind enemy lines, and other elite units.The IDF has destroyed 34 terrorist tunnels in Gaza and five cross-border attack tunnels.Seventy Palestinian combatants have been killed – 20 of them on Saturday.Thirteen terrorists have been arrested and taken for questioning in Israel.Gaza officials said at least 335 Palestinians, including 70 children, have been killed in the 12-day conflict - about 100 in the last 48 hours alone.Over the weekend the IDF struck more than 450 terrorist targets in Gaza from the air, sea and land.In different incidents on Friday: • The air force struck a mortar- launching cell that was targeting IDF ground forces in Gaza.• In the afternoon, a terrorist armed with five grenades approached soldiers and requested medical attention pretending to be unwell.When the army dispatched a medic, he tried to throw a grenade at the soldiers, who opened fire and killed him.• An IDF tank activated its Windshield protection system when an anti-tank missile was fired at it.• Army sources said Hamas and Islamic Jihad have placed gunmen in the homes of northern Gaza civilians who had evacuated them.• IDF units seized positions in northern, central and southern Gaza and traded fire with terrorists overnight between Thursday and Friday.• Fourteen Palestinian combatants were killed in the first night of the ground offensive.“We are focusing on three efforts,” the IDF source said. “The first is continued air strikes. The second is the taking over of [tunnel] targets [by ground units]. The last is preparing the next stage of this operation.”The ground forces are focusing on destroying Hamas’s extensive tunnel network. In their first few hours in Gaza, they were engaged by gunmen and returned fire. In some cases, bombs were set off near the approaching army forces.The source described the resistance encountered by the IDF as “low,” adding that the massive waves of fire launched by artillery and air units before the entrance of ground units help ensure that Hamas “kept its head down.”“Hamas was surprised by the patience of the Israeli public, and by the performance of Iron Dome,” the source said.“It took Hamas years to plan the tunnel attack on Kibbutz Sufa,” he added, referring to an attempt on Thursday by Hamas to send 13 men to carry out a massacre on the kibbutz, before they were spotted and targeted with an air strike.The air force hit 103 targets overnight between Thursday and Friday, including 20 underground rocket launchers and six terrorist headquarters.Since the start of the operation, the IAF has struck 2,150 targets, including 1,160 underground launchers, 200 command and control centers, nine training camps and 43 Hamas regime buildings.The IAF also struck rocket launching squads as they were preparing to fire into Israel, the source added.Hamas responded with rocket fire on several Israeli areas, in some cases overnight. Air force planes and artillery batteries immediately struck areas after they were used to fire on Israel.“We are directing our firepower at operatives, tunnels and infrastructure,” the source explained. He added, “Very large intelligence capabilities are being activated and new targets are being acquired.”The cabinet has authorized the IDF to call up another 18,000 reservists for Operation Protective Edge.