The human rights organization Gisha charged on Thursday that the refusal of the army to allow fuel, cooking gas and other commodities into the Gaza Strip constitutes collective punishment of 1.5 million civilians. Israel sealed the border crossings into Gaza on November 4 in response to the renewal of rocket and mortar attacks against civilian targets in Israel by Palestinian terrorist groups. These attacks followed an IDF operation inside Gaza to destroy a tunnel built by Hamas, allegedly to kidnap a soldier. Four armed Hamas members were killed during the operation. Israel allowed 30 truckloads of humanitarian aid into the Gaza Strip on November 17. It has also allowed the entry of 650,000 liters of diesel fuel, which is required to operate the Gaza electric plant. Gisha pointed out that the state promised the High Court of Justice to supply 2.2 million liters of industrial diesel each week as a minimum humanitarian requirement. "The consequences for the 1.5 million residents of Gaza are grave," wrote Gisha lawyer Yadin Ilem. Specifically, Ilem cited "disruptions in the operation of vital systems, such as the water supply [and] hospitals, [and the withholding] of food supplies to the needy and vital goods for the health and well-being of the residents of the Gaza Strip." In a letter dated November 16 and sent to Ahaz Ben-Ari, the legal adviser of Israel's defense ministry, Gisha charged that in the past, when the army closed the border crossings, it was said to have been due to a specific security threat against soldiers and employees at the crossings. This was clearly not the case now, Ilem charged. In response to an earlier letter from Gisha, Ben-Ari wrote: "The supply of industrial diesel to the Gaza Strip has been withheld in the past few days because of the salvoes of Kassam rockets that have been fired from the Gaza Strip into Israel. This fire, which is aimed at civilian targets inside Israeli territory, also endangers the activities involved in supplying the goods, including fuel." Gisha wrote that Ben-Ari had failed to explain the connection between the firing of rockets into Israel - which it confirms is illegal because the weapons are aimed at innocent Israeli civilians - and the supply of fuel and other goods that are vital to civilians in Gaza. Gisha demanded to know the army's considerations in deciding to close the crossings; whether it believed the closure would deter the political echelon and the terrorists in Gaza from firing rockets; and whether the closure was a deterrent or a punitive act. Meanwhile, a Kassam rocket fired from northern Gaza on Thursday afternoon landed in the Sha'ar Hanegev region. It came to earth in an open area, and no injuries or damage were reported. Jerusalem Post staff contributed to this report.