Two Palestinians were killed by an Israeli drone strike on southern Gaza early Monday, medical sources said, just hours after two others were killed in a separate attack. Gaza Strip health services spokesman Ashraf al-Qudra said two Palestinians were killed and two others wounded in the attack east of Rafah. Ezzedine al-Qassam Brigades, Hamas's military wing, said meanwhile that six of their men were killed by the Israeli strike on Rafah. Witnesses said Qassam members were killed when a tunnel had collapsed on them following the Israeli strike.