The IDF was forced on Sunday to halt deliveries through the Karni border crossing and the Nahal Oz fuel terminal, as vehicles came under Palestinian mortar shell fire whilst attempting to transfer food and fuel to Gazans, reported Israel Radio. Police said that approximately 50 trucks of supplies were forced to turn back as a result of the barrage. Meanwhile, Hamas has started using police cars to ferry around Palestinians because of severe fuel shortages. Orange stickers reading, "We are ready to drive you for free," were affixed to blue units of the Hamas-run police force. Israel has restricted fuel supplies to Gaza in an attempt to pressure Palestinian terrorists to halt their rocket barrages at nearby Israeli communities. Although Hamas complains bitterly about fuel shortages, it is widely believed that it has hoarded supplies for its own use - especially now that it is offering its vehicles to ferry people for free. However many residents, hit by lack of other transport, were just grateful for the service. Suzan Salman, 48, used one of the police cars to take her to a downtown hospital, where her daughter had just given birth. "It's good that we have somebody who cares about us," the grandmother said. "We are here to serve our people," said Mohammed Hamza, a 25-year-old Hamas policeman. However, one Gaza resident, a 33-year-old man who gave his name only as Jamal, refused the offer, saying it was a publicity stunt. He blamed Hamas for the fuel shortages. "They want to fool the people," he said, declining to give his last name for fear of reprisals from the terrorist group. "They are trying make the people forget who is behind our suffering." UN official Chris Gunnes said Sunday that the world body did not receive fuel and had to cancel its distribution of food to Palestinian refugees set for Monday. He refused to say who he thought was responsible for the shortage. Transport has come to a near halt in Gaza since Israel reduced supplies of gasoline and diesel fuel. Shortages have sent black market prices for gasoline from $6.30 per liter to $7.20/liter. For the past month, most Gaza residents have walked, cycled or adapted their cars to run on bottled cooking gas or vegetable oil in order to get around.