Dozens of Israeli fighter jets have attacked more than 100 targets in Gaza, the Israel Defense Forces (IDF) said on Tuesday morning, with over 50 people reported to have been killed.

The Israeli Air Force struck tunnel shafts and military installations used by Palestinian extremist organization Hamas among other targets, according to the IDF.

At least 52 people were killed in the attacks, according to the Hamas-controlled Health Ministry in Gaza.

A terrorist cell in Jabalia that had attempted to plant explosives near an Israeli tank was eliminated overnight, the IDF report said, adding that ground troops had targeted the fighters before they were killed by a fighter jet.

It was not possible to independently verify the claims.

Hamas fighters had also been killed the previous day in the southern city of Khan Younis, the army added.

On Tuesday morning, the Israeli army also reported renewed rocket alerts, with sirens sounding in communities along the border with Gaza.

An Israeli website which gives live rocket alert updates corroborated the army’s information.

Israel’s army has stepped up its operations against Hamas after Israeli Prime Minister Benjamin Netanyahu said during a troop visit to the sealed-off coastal strip that Israel would “intensify the fight in the coming days.”

Netanyahu spoke of a long battle, the end of which was not in sight. Hamas, for its part, rejected a temporary ceasefire in the war and called for a permanent ceasefire. It was reacting to an Arab media report according to which Egypt had drawn up a draft for a gradual end to the war.

Israel’s all-out assault on the Gaza Strip was triggered by the terrorist attack carried out by Hamas and other extremist groups on October 7 in Israeli border communities near Gaza. More than 1200 people, mainly civilians, were killed.

Israel responded with massive airstrikes and a ground offensive in which, according to the Hamas-controlled health authority, more than 20,600 people have been killed and more than 54,500 injured so far.

It is not possible to independently verify the figures but various UN bodies, in the past, have said that figures from the Gaza health authorities are credible.

Meanwhile, an employee of the UN’s Office for the Coordination of Humanitarian Affairs (OCHA) has described what she saw at the Al-Aqsa hospital in Gaza as “absolute carnage.”

Gemma Connell told BBC that there were many injured with “extremely severe wounds but [who] cannot be treated because there are so many people in front of them in the line for surgery, and the hospital is absolutely overloaded.”

“Tragically I saw a nine-year-old boy with a devastating head injury who passed away,” Connell was quoted as saying on Tuesday.