Jerusalem ( CNN ) -- The Palestinian Authority 's president has called for an emergency meeting of the Arab League over the escalation of conflict between the Israeli military and Gaza-based militants , the Palestinian Authority-run news agency WAFA said on Saturday . President Mahmoud Abbas asked the Cairo-based organization to convene on Sunday , PLO Executive Committee member Saeb Erakat said , according to WAFA . In the latest fighting on Saturday , Israeli air force struck and killed three Hamas personnel in southern Gaza , according to both the Israeli military and Palestinian medics . The Israel Defense Forces said the people were a senior Hamas military wing leader and his two bodyguards . In another incident , a Palestinian man died of wounds in an early evening airstrike in the Zeitoun area of Gaza City . About 42 rockets and mortars had been fired into Israel on Saturday , including 10 longer-range Grad rockets , but no injuries have been reported , said Israeli police spokesman Micky Rosenfeld . The IDF said in a statement about 50 rockets and mortars were fired at Israel since Saturday morning . It said aircraft and armored forces targeted 11 squads of `` terrorists '' in the northern and southern Gaza Strip and 15 `` terror activity sites , '' including `` terror infrastructure sites , Hamas outposts , smuggling tunnels and weapons manufacturing and storage facilities . '' The developments are the latest in a three-day tide of intensified violence that began on Thursday , when Hamas militants attacked an Israeli school bus that critically wounded a 16-year-old boy and prompted Israeli retaliatory strikes against fighters in Gaza . The three-day death toll in Gaza rose to at least 18 , 10 militants and eight civilians . Since Thursday , Palestinian militants have fired dozens of mortars and rockets into southern Israel . On Friday , Israeli Prime Minister Benjamin Netanyahu said the attack on a civilian bus `` crossed the line '' and that `` whoever tries to hurt and murder children will have no immunity . '' The mounting death toll in Gaza represents the highest number of Palestinian casualties since the 2008-09 Israeli military offensive , when more than a thousand Palestinians were killed . The offensive was prompted by daily missile bombardments from Gaza into southern Israeli communities , which Israel intended to end . Now , there is increasing speculation in both Israeli and Palestinian media that another large-scale Israeli military operation could be launched soon . In a Friday letter to the U.N. Security Council , Riyad Mansour -- permanent observer of Palestine to the United Nations -- charged Israel with using `` indiscriminate and excessive force '' and asked for the world body to intervene to `` prevent the slaughter of more innocent civilians . '' A Hamas official vowed Saturday to widen the scope of the group 's attacks on Israel if Netanyahu did not agree to halt airstrikes on Gaza . Hamas spokesman Sami Abu Zuhri blamed Israel for the surge in violence and said Hamas would do what was needed to protect Palestinians in Gaza . Abu Obeida , spokesman for the Hamas military wing , the Ezzedeen Al-Qassam Brigades , told reporters in Gaza City on Saturday that his group would continue to wage a fight until Palestinians cast off the Israeli occupation and wrested away their lands . He said it was impossible to speak about any sort of calm between Hamas and Israel while there was aggression being committed against the Palestinian people . Israeli officials have cited various precautions to avert casualties . They include early warning systems , road closures near the Gaza border and the use of bomb shelters , Rosenfeld said . The Israeli military said Saturday that its newly deployed anti-rocket defense system known as the Iron Dome successfully intercepted Grad rockets that had been fired from Gaza Friday and Saturday . Over the past 48 hours , `` terrorist organizations '' in Gaza have fired more than 120 Grad missiles , rockets and mortars at Israel , the IDF said . In a statement released Saturday , the Israeli military said it `` continued striking terror sites in the Gaza Strip '' in coordination with Israel 's domestic security agency , the Shin Bet . Journalist Talal Abu Rahma contributed to this report .
three dead in Gaza airstrikes . Rockets and mortars fired into Gaza , police say . Palestinian leader calls for Hamas sit-down . The Israeli military killed 1 Hamas personnel the past 48 hours , officials say .