GAZA CITY, Palestinian Territories (AFP) — Israel's military on Thursday expanded ground operations across Gaza, after it reported missiles intercepted from Yemen and Hamas militants said they fired rockets towards Tel Aviv.

The rocket fire from Hamas was its first military response to the growing civilian death toll from Israel's resumption of aerial bombardment and ground operations in Gaza this week.

The offensive has drawn widespread condemnation and shattered a relative calm in the war-ravaged Palestinian territory where a ceasefire began on 19 January. Talks on extending the truce reached an impasse, and Israel resumed intensive bombing of Gaza on Tuesday.

Late Thursday, the military said troops had begun "conducting ground activity" in the Shabura area of Rafah, Gaza's southernmost city near the Egyptian border.

"As part of the activity, the troops dismantled... terrorist infrastructure," the military said in a statement, adding that "troops are continuing ground activity in northern and central Gaza."

Israel earlier said it had closed off the territory's main north-south route as part of expanding ground operations that resumed on Wednesday.

Gaza's civil defense agency said 504 people had been killed since Tuesday, including more than 190 under the age of 18.

The toll is among the highest since the war started more than 17 months ago with Hamas' attack on Israel.

The armed wing of Hamas, the Ezzedine al-Qassam Brigades, said it fired rockets at Israel's commercial center in response to "massacres" of Gaza civilians.

The Israeli army said it intercepted a missile launched from Yemen, claimed by Iran-backed Houthi rebels who say they act in support of the Palestinians, for the second time within a day.

United States President Donald Trump "fully supports" Israel's renewed Gaza operations, White House Press Secretary Karoline Leavitt told reporters when asked if he was trying to get a Gaza ceasefire back on track.

Israel's military said an air strike had "in recent days" killed Rashid Jahjouh, the head of Hamas' internal security agency.

In Beit Lahia, northern Gaza, Alaa Abu Nasr said 17 members of his family were killed in an air strike.

"They are targeting civilians, not fighters," he said among the rubble.