During the operation , Hamas , the al-Qassam Brigades and the Palestinian Islamic Jihad ( PIJ ) further intensified Cause_change_of_strength their rocket attacks Attack on Israeli cities and towns , in an operation code named Operation Stones of Baked Clay ( , `` ḥijārat sijīl '' ) by the al-Qassam Brigades , firing Use_firearm over 1,456 rockets into Israel , and an additional 142 which fell Motion_directional inside Gaza itself .