In preparation for a large-scale Palestinian protest march planned for Gaza on Monday, security forces mobilized along the security fence Sunday night in an effort to head off a replay of last month's Rafah border-storming at the Erez or Kissufim crossings. An artillery battery was moved to the Gaza border for the first time in months, and rules of engagement were reviewed as troops prepared for the demonstration Hamas is calling a "human chain." A joint statement issued by the Foreign and Defense ministries blamed Hamas for fanning the flames and endangering Gazan civilians. "Hamas, not for the first time, is orchestrating a premeditated effort to put civilians on the front line. Israel does not get involved in demonstrations that occur within the Gaza Strip, but Israel will defend itself and prevent incursions into its sovereign territory. Israel is working to prevent an escalation, but has made it absolutely clear that if there is an escalation, the responsibility will be entirely on Hamas's shoulders," the statement read. The IDF was unwilling to confirm or deny a Channel 2 news report saying soldiers would be instructed to fire at protesters' legs should they approach the security fence, in order to prevent a recurrence of what happened at the Gaza-Sinai border on January 23. Hamas announced Sunday that it would mobilize the mass demonstration along the Salah-a-Din Route from Rafah on Gaza's Egyptian border to Beit Hanun in the north, to protest the continued embargo placed on the Strip. The protest is geared to attract more international attention than previous protests against the sanctions, due to its size and the photographic value of a chain stretching more than 60 kilometers along the entire length of the Gaza Strip. But security forces are concerned that the protesters - or organizers - will not be satisfied with the symbolic imagery and might try to make good on threats issued by a Hamas leader last month that the Erez crossing would become the next Rafah. In a worst-case scenario, Hamas activists could motivate the crowds to storm the Gaza security fence, particularly at "weak spots" where Israeli communities or army bases abut the strip. Areas such as the Erez crossing, Kissufim, Nahal Oz and Netiv Ha'asara are considered to be particularly at risk. IDF Chief of General Staff Lt.-Gen. Gabi Ashkenazi held a situation assessment with officers on Sunday night, including representatives of the Home Front Command, to finalize preparations for Monday's IDF response. Israel Police chief Insp.-Gen. David Cohen also held a late-night assessment, in which police decided to raise the national alert level. Some 6,500 police officers, one senior officer said, would be deployed to the Southern District on Monday morning to maintain order. While some Hamas officials have denied organizing an attempt to breach the border, others have hinted that such a human surge - involving women and children - might in fact occur. "The next time Gazan residents protest the ongoing siege, they will do so on the border with Israel, and not on the border with Egypt," Israel Radio quoted one senior Hamas official as saying on Sunday. Over the weekend, the IDF was already rushing large forces to the Gaza border in anticipation of civilian unrest after gasoline supplies in the territory ran out on Saturday for all but emergency service vehicles. Immigration Absorption Minister Ya'acov Edri (Kadima) said Sunday that the government was ready for any scenario resulting from Palestinians trying to breach the border crossings. Also Sunday, an all-day IDF operation in the southern Gaza Strip, near the defunct Dahiniye airstrip, bore fruit in the afternoon, when Givati infantry, Armored Corps units and combat engineers uncovered five tunnels used to smuggle arms from Sinai into Gaza. In the course of the operation, 50 Palestinians were detained for questioning on suspicion of involvement in a terrorist organization. Six Kassams were fired Sunday at the Negev.