The IDF is concerned that Hamas is planning to resettle thousands of displaced Gazans in caravans and temporary homes along the border with Israel, defense officials said on Sunday. The army learned recently of the plan, initiated by Hamas Housing Minister Yousef al-Mansi, under which thousands of Palestinians who are waiting for their homes that were damaged during Operation Cast Lead to be repaired will be housed in temporary structures and caravans along the border with Israel. The IDF believes that Mansi plans to set up the temporary villages to serve as obstacles in the event that Israel sends ground forces into Gaza. The border villages will also likely serve as cover for tunnels that Hamas will dig under the security fence and into Israel to carry out attacks. "This is part of Hamas's overall strategy to use built-up areas to hide in and to launch attacks," a senior defense official said. "This basically means that Hamas will want to use the people it places there as human shields against Israel." On Sunday, the IDF escalated its response to the Kassam rocket fire from Gaza and for the first time since Operation Cast Lead bombed a weapons manufacturing plant in the heart of Gaza City. The upgrade in the army's response followed last week's decision to begin to target rocket launchers as well as terrorist cells that are preparing to fire rockets into Israel.