Israel says it is conducting "extensive strikes" against Hamas in Gaza, throwing doubt on the fragile ceasefire.
In a statement, the Israel Defence Forces and Israeli Security Agency said early on Tuesday it was "currently conducting extensive strikes on terror targets belonging to the Hamas terrorist organization in the Gaza Strip."
The Civil Defence in Gaza said a number people were "trapped under the rubble of homes that were bombed in various areas" of the enclave.
Palestinian children struggle while waiting for donated food at a distribution centre in Beit Lahiya, northern Gaza Strip.
Palestinian children struggle while waiting for donated food at a distribution centre in Beit Lahiya, northern Gaza Strip. (AP)
CNN stringers in Gaza reported the sounds of strikes in multiple locations.
Israeli Prime Minister Benjamin Netanyahu and Defence Minister Israel Katz ordered the operation, accusing Hamas of "repeatedly" refusing to release hostages and rejecting mediation offers.
"The IDF is currently attacking targets of the Hamas terrorist organization throughout the Gaza Strip, with the aim of achieving the war goals as determined by the political echelon, including the release of all our hostages — living and dead," said a statement from the Prime Minister's Office.
"From now on, Israel will act against Hamas with increasing military force."