Residents of Rafah and Khan Younis in the Gaza Strip claimed Sunday evening to have received telephone calls from Israeli security forces warning them to evacuate areas from which gunmen are operating.
According to the civilians, the messages said "all those residing near a terror hub, a tunnel or a weapons cache must leave the area immediately."
Some Palestinians had reportedly evacuated their homes for fear of Israeli retaliation following Sunday morning's rocket and mortar barrages on the Negev region. A total of four Qassams and 13 shells were fired at Israel since the morning hours.
Ynet has learned that Hamas offices in the Strip had also been cleared in light of the attacks and the consequent threats issued by Israeli ministers.
Prime Minister Ehud Olmert clarified at the start of the weekly cabinet that Israel would respond forcibly to Sunday morning's rocket fire.
"The cabinet's position from the first moment was that if the south's residents are fired on, our response will naturally be disproportionate," he said.
According to Hamas, Fatah is launching the attacks with the aim of weakening Hamas and dragging Israel into a fresh conflict in Gaza.
News agencies contributed to the report