Three Kassam rockets fired from Gaza landed in open areas in the Sdot Negev region on Friday morning. The terrorists fired the rockets as Purim festivities were underway in the area. No one was wounded and no damage was reported. Aside from the Kassam attacks, this year's Purim celebrations across the country were clouded by security warnings. The security establishment reported seven specific warnings of attacks, including suicide bombings, shooting attacks and kidnapping attempts. There were also dozens of non-specific warnings. The high alert level was due in a large part to the end of the 40-day mourning period for slain Hizbullah terror chief Imad Mugniyeh. Israel denied involvement in the assassination, but Hizbullah threatened to avenge his death with an attack on Israeli targets. Police spokesman Micky Rosenfeld said the alert level Friday was one below the maximum. Meanwhile, terrorist training in Gaza took its toll on Hamas Friday morning as one of the group's operatives was killed and two were injured in an accidental explosion at a facility in the southern Gaza neighborhood of Khan Yunis, Palestinians reported. On Thursday, two people were killed in a similar incident in a Hamas installation in Zeitun. AP contributed to this report.