Prime Minister Benjamin Netanyahu said on Saturday that Israeli forces had unleashed the second phase of the Gaza war as they pressed ground operations against Hamas militants, vowing to “destroy the enemy above ground and below ground.”

Gaza’s besieged people had barely any communications with the outside world as Israeli jets dropped more bombs on the Hamas-ruled Palestinian enclave and military chiefs said a long-threatened ground offensive was gearing up.

Speaking at a press conference in Tel Aviv, Netanyahu warned Israelis to expect a “long and hard” military campaign but stopped short of calling the current Israeli ground incursions a full-scale invasion.

He reiterated Israel’s appeal to Palestinian civilians to evacuate the northern Gaza Strip where Israel was focusing its attack, and vowed that every effort would be made to rescue the more than 200 hostages held by Hamas.