A mass grave has been dug inside Al-Shifa Hospital in Gaza to bury dozens of corpses after Israeli forces banned the Red Cross from collecting the bodies, according to Dr. Munir Al-Bursh, the director general of the Palestinian Health Ministry.

"There are approximately 100 corpses lying on the hospital courtyard that have rotted and decomposed," Al-Bursh told Al-Hadath TV on Tuesday, speaking from inside the hospital, the largest in Gaza. "We are walking on worms and we fear there will be an epidemic."

Medical staff and people sheltering inside the medical complex have dug a "large hole" to bury the dead bodies, he said. Dozens of other bodies stored in refrigerators at the facility will also be buried in the mass grave, he said.

"Israel tanks are at the gates of the hospital and we are burying bodies under gunfire and with tanks around," Al-Bursh said.

The hospital ceased to function on Saturday after it ran out of fuel, and staff and health ministry officials inside say the facility has been under siege by Israeli forces for five days, with drones and snipers firing into it.

"We are trying to dig a mass grave to bury the martyrs inside Al-Shifa Hospital. Our efforts to remove the bodies of the martyrs from Al-Shifa complex have failed," said Dr. Youssef Abu Al-Rish, undersecretary of the Hamas-run Gaza Ministry of Health.

Israeli officials have said Hamas is operating a command center from under the hospital, something denied by Hamas.

-ABC News' Ayat Al-Tawy and Morgan Winsor

One of two humanitarian corridors that the Israeli military has temporarily opened in the Gaza Strip on Tuesday is less than 1.5 miles long, according to an executive officer of an Israeli battalion in charge of the route.

The officer told ABC News that the corridor is a 2-kilometer stretch of Salah al-Din, the main highway connecting the north and south of Gaza. He said his troops have come under sniper fire and that "there were casualties."

The Israeli military has distributed leaflets directing civilians in the north to routes that take them to the corridors, offering safe passage to evacuate to the south of the war-torn enclave within a designated window of time on Tuesday.

-ABC News' Matt Gutman, Becky Perlow and Juan Rentaria

The Israel Defense Forces announced Tuesday morning that it "is in the process of coordinating the transfer of incubators from a hospital in Israel to Gaza."

"We are doing everything we can to minimize harm to civilians, assist in evacuation, and facilitate the transfer of medical supplies and food," the IDF wrote in a post on X, the social media platform formerly known as Twitter. "Our war is not with the people of Gaza."

The IDF also shared a video message from Shani Sasson, spokesperson for COGAT, the Israeli defense body that handles Palestinian civil affairs.

"The pedantic ward at Shifa Hospital in Gaza City needs assistance. Israel is ready to assist," Sasson said in the video. "We made a formal offer to health officials in Gaza to transfer incubators into Gaza Strip to assist the paediatric ward of Shifa Hospital. Extensive offers are underway to insure that these incubators, right here behind me, can reach babies in Gaza without delay. Our war is against Hamas and not the people of Gaza."

It was unknown whether the process to transfer incubators was underway and there was no confirmation of Israel's offer from health officials or medical staff in the Gaza Strip. It was also unclear how the incubators would be powered at Gaza's hospitals with little to no electricity and fuel.

The announcement came amid worldwide calls to save dozens of premature newborn babies at Gaza's second-largest hospital.

Al-Shifa Hospital in Gaza City had been struggling to run with limited fuel for days as doctors warn of its imminent collapse. On Friday, fighting in the area intensified and a strike hit the courtyard outside the hospital.

Three of the 39 babies that were being cared for in Al-Shifa's neonatal unit have died since their incubators stopped working on Saturday, according to the hospital's head of plastic surgery, Dr. Ahmed Mokhallalati. The hospital staff has been trying their best to look after them, swaddling them and using what power is left to heat the room they are in.

In recent days, several hospitals across Gaza said they have been under attack as heavy fighting occurs between Israeli troops and the militant group that rules the enclave, Hamas. The IDF alleges that Hamas has placed its command centers in tunnels under hospitals in Gaza and is deliberately sheltering behind Palestinian civilians -- claims which the group denies.

-ABC News' Zoe Magee, Jordana Miller and Morgan Winsor

The Israel Defense Forces announced Tuesday the temporary opening of evacuation corridors in the war-torn Gaza Strip to allow more people in the north of the Hamas-run enclave to move south.

A "safe passage" will be open "for humanitarian purposes" via the Salah al-Din highway toward the area south of Wadi Gaza on Tuesday between 9 a.m. and 4 p.m. local time, according to the IDF.

The IDF said it will also temporarily suspend military activities "for humanitarian purposes" in the neighborhoods of Al-Daraj and Al-Tuffah on Tuesday between 10 a.m. and 2 p.m. local time.

"Please, for your safety, join the hundreds of thousands of residents who have moved south in recent days," the IDF said in a statement. "We encourage you to seize the time and move south!"

The IDF also urged Gaza residents to "not surrender to Hamas," alleging that the militant group "has lost control over the northern Gaza Strip area and is trying to do everything it can to prevent you from moving south and protect yourselves."

-ABC News' Jordana Miller

Patients and doctors evacuated the Al-Shifa hospital on Saturday, after the Hamas-run Gaza Health Ministry claimed Israel forced them to leave. The IDF released a statement denying it ordered the evacuation, but in a Friday briefing another spokesperson said the IDF was urging anyone left in Al-Shifa hospital to leave and that it hoped it would take place in the "next few hours."

Doctors described their exodus from the hospital to ABC News, with Dr. Ahmed Mokhallalati -- who is still in the hospital -- saying "all critical ICU patients have died. The situation is terrifying."

"Today early in morning people were forcefully evacuated from the hospital, with absolutely no plan of evacuation of the patients and the medical staff. Most of the civilians together with most of the staff left the hospital," Mokhallalati said.

Mokhallalati said there are around 300 patients, who cannot move, and less than 50 medical staff still in the hospital.

"There are still 33 premature babies in the hospital -- one baby died yesterday, and two babies were taken by their parents to evacuate with them. There is only one neonatologist and one nurse with them," he added. The Israelis have provided only three transport incubators for 33 babies. So, if they tell us 'you have to evacuate now,' I have no idea how to evacuate them."

Dr. Adnan Al-Barash, head of the orthopedic department at Al-Shifa Hospital, told ABC News that the "Israeli army forced us to leave the hospital at gunpoint."

"The path for us to walk was set out among the tanks, we had elderly, wounded… The scene was very tragic and sad," Al-Barash said.

"We went out between the tanks, and we could not get the wounded out on the broken roads and we could not move wheelchairs for the wounded," he added.

-ABC News' Dragana Jovanovic and Zoe Magee