Cairo: Three sons of Hamas leader Ismail Haniyeh were killed in an Israeli airstrike in Gaza on Wednesday, the Palestinian Islamist group and Haniyeh’s family said.The three sons – Hazem, Amir and Mohammad – were killed after the car they were driving in was bombed in Gaza’s Al-Shati camp, Hamas said. Two of Haniyeh’s grandchildren were also killed in the attack and a third was wounded, Hamas media said.”Our demands are clear and specific and we will not make concessions on them. The enemy will be delusional if it thinks that targeting my sons, at the climax of the negotiations and before the movement sends its response,The blood of my sons is not dearer than the blood of our people,” said Haniyeh, who is based abroad in the Gulf Arab state of Qatar.Haniyeh has been the tough-talking face of Hamas’ international diplomacy as war with Israel has raged back in the Gaza Strip, where his family home was destroyed in an Israeli airstrike back in November.