JERUSALEM >> Israeli forces were expanding their offensive in the Gaza Strip on Sunday, taking control of more territory and issuing new evacuation orders for residents who had only recently returned to their homes.

The Israeli military renewed its offensive in Gaza this past week after talks to extend a fragile, temporary ceasefire that went into effect in mid-January reached an impasse.

Amid the escalation in fighting and evacuation orders, Gaza’s Health Ministry said Sunday that the death toll in the enclave since the war started had surpassed 50,000 people — including 39 people killed in Israeli bombardments over the past day. The ministry’s figures do not distinguish between civilians and combatants.

On Sunday, Israel said that its operations had moved into additional areas in the north and south of the enclave.

Israel said that its troops had begun operating in Beit Hanoun, in northern Gaza, to expand a buffer zone. The military also said that it had carried out more airstrikes against Hamas targets and infrastructure and that it was allowing people to evacuate.

The military also separately issued an evacuation order for the Tal al-Sultan neighborhood of the southern city of Rafah, telling residents to leave on foot along a specific route and barring the movement of vehicles.

The Rafah municipality said in a statement that thousands of families were being forced to flee on foot under bombardment during the holy Muslim fasting month of Ramadan. That left them homeless amid a severe shortage of basic necessities and tents because of the Israeli government’s closure of the crossings into Gaza, the municipality noted.

“I am hearing lots of gunfire and bombing,” Riham Abu Marzouq, 22, said in a phone call Sunday afternoon while fleeing her home in Rafah with nine relatives. “We are now walking,” she added, panting and struggling to catch her breath.

Hamas announced that Israel had killed a senior member of its political bureau, Salah al-Bardawil, overnight. The group said that al-Bardawil, one of the militant group’s prominent spokespeople, had been killed along with his wife in a strike on their tent in Muwasi, an area in southern Gaza that the Israeli military had designated as a humanitarian zone and to which it directed residents of Tal al-Sultan on Sunday.

After noon Sunday, the military said that its troops had completely encircled Tal al-Sultan, had eliminated several fighters and had raided a site that it said had been used over the past few months as a Hamas command and control center.

Neither claim could be independently verified.

The Palestinian Civil Defense in Gaza warned Sunday of “imminent danger threatening the lives” of more than 50,000 people in Rafah.

“The situation in Rafah is very difficult,” said Huthayfah Lafi, a resident of the southern city who lives near Tal al-Sultan. He said he had decided not to evacuate the area Sunday “until the situation becomes more clear” because “we have nowhere else to go.”

And the Palestinian Red Crescent said that it had lost contact with four of its ambulances that it said were trapped in Rafah and had crew members wounded by Israeli gunfire. The Israeli military said that it was looking into the reports but did not immediately provide any further comment.

Mohammed Abu Taha, 42, said his sister Sanaa and her family had been able to return to their home in Rafah only in the past few weeks. Around dawn Sunday “they were surprised by Israeli tanks advancing toward them,” he said, relaying what his sister had told him over the phone while fleeing on foot to the city of Khan Younis, where he has been sheltering.

“They were only allowed to carry a small bag,” said Abu Taha.

Late Sunday, the Israeli military said in a statement that it struck “a key terrorist” in Hamas who it said was operating inside the Nasser Hospital compound in southern Gaza, without naming the target of the strike. The military said it used “precise munitions in order to mitigate harm” to the surrounding area.

Health authorities in Gaza said in a statement that Israeli forces had targeted the surgical department in the medical complex, which housed many patients, and that a large fire broke out as a result. In separate statements, the Gaza Health Ministry condemned the direct targeting of the hospital, which it said resulted in the death of two patients there, among them a 16-year-old discovered amid the rubble, and the injury of several others, including medical personnel.