Israel says it has resumed its raids in Gaza because Palestinians have ignored the 24-hour extension of a humanitarian ceasefire that was requested by the United Nations.
The military said Sunday "following Hamas' incessant rocket fire throughout the humanitarian window, which was agreed upon for the welfare of the civilian population in Gaza, the IDF will now resume its aerial, naval and ground activity in the Gaza Strip."
Palestinians say three people have been killed in Gaza since the shelling resumed.
Militants in the Gaza Strip hit Israel with a barrage of rockets Sunday, several hours after Israel agreed to pause the fighting.
The Israeli military says seven rockets were fired at southern Israel early Sunday. It says five rockets landed and two were downed by Israel's Iron Dome air defense system.
Israel had agreed Saturday to continue the original 12-hour truce in Gaza another 24 hours through Sunday at midnight local time ( 2100 UTC). An Israeli official says the United Nations asked for the extension and the Cabinet agreed.
The official says Israel would respond to Hamas rocket fire during the extension and continue to search for and destroy tunnels Hamas uses to smuggle weapons and fighters. Hamas rejected the extension, saying Israel first had to withdraw its forces from Gaza.
Hamas militants fired several rockets into Israel shortly after the original 12-hour cease-fire ended. Israeli forces did not respond.
Saturday's truce gave Gaza residents a chance to return to their homes to see what is left after nearly three weeks of Israeli airstrikes in response to Hamas rocket fire. Some were able to salvage a few belongings while others found their homes destroyed.
Palestinians say their death toll has exceeded 1,000. Most of those killed were civilians, including many children. Israel says 43 Israeli soldiers and two civilians have died.
Several thousand people gathered in Tel Aviv Saturday evening, calling for an end to Israel's military campaign in Gaza.