(Reuters) - Israel's military pounded the Palestinian enclave of Gaza on Sunday and killed hundreds of people a day after a surprise attack by Hamas militants left some 700 Israelis dead, the worst attack on Israeli soil in decades.

ISRAEL TARGETS GAZA

*Israeli bombing on Sunday targeted the homes of Hamas officials, but also hit housing blocks, tunnels and a mosque, killing at least 400 people. The retaliation was complicated by an unknown number of Israeli hostages held in the area.

*Israel's Defense Minister Yoav Gallant said that the Israeli campaign in Gaza would "change reality for generations."

*The Palestinian Foreign Ministry denounced Israel's attacks on Gaza as a "barbarous campaign of death and destruction."

HAMAS PLANNING

*Hamas carried out a careful campaign of deception to pull of its stunning attack, accounts from Hamas and Israeli sources show.

UNITED STATES AID

*President Joe Biden told Israeli Prime Minister Benjamin Netanyahu on Sunday that the U.S. was sending additional assistance for Israel's military.

*U.S. Secretary of Defense Lloyd Austin said that the U.S. will send multiple military ships and aircraft closer to Israel.

(Compiled by Brad Brooks; Editing by Andrea Ricci)