Israel-Gaza updates: More hostages released, including 4-year-old American girl

Dozens of premature babies are expected to be transported from the war-torn Gaza Strip into neighboring Egypt on Monday to receive emergency medical treatment.

The babies arrived on Gaza's side of the Egyptian-controlled Rafah border crossing on Monday afternoon. Egyptian television footage showed Egyptian doctors moving the babies from Palestinian ambulances into mobile incubators. The infants will then be taken via Egyptian ambulances to nearby hospitals in the North Sinai province of northeastern Egypt, which shares a border with Gaza.

The Palestinian Red Crescent Society confirmed that its ambulance teams had transferred 28 premature babies to Egyptian medics at the Rafah border crossing on Monday afternoon. The process was done in coordination with the World Health Organization and the United Nations Office for the Coordination of Humanitarian Affairs, according to the Palestinian Red Crescent Society.

At least 12 of the babies who are said to be in deteriorating condition will be airlifted to Egypt's capital, Cairo, according to Egyptian media.

Rick Brennan, regional emergency director for the WHO's Regional Office for the Eastern Mediterranean, said in a statement, "We are cautiously optimistic that they will do well but we have to watch them very, very closely. They can still develop further complications. ... They are not out of the woods yet by any means. So they will need that intensive care for some time to come."

Three babies were in stable condition and didn't need to be transferred to Egypt for more treatment, according to the World Health Organization.

Earlier Monday, Egyptian TV footage showed medics with incubators at the Rafah border crossing as they prepared to receive the tiny patients. Egypt's heath minister was also seen on site inspecting the preparations.

The babies were evacuated on Sunday from Gaza's largest medical complex, Al-Shifa Hospital in Gaza City, and brought to Emirati Hospital in Rafah, a city in southern Gaza close to the border with Egypt.

Like many hospitals in Gaza, Al-Shifa has been struggling to function with a lack of electricity as well as limited fuel and medical supplies amid Israel's continued bombardment of the territory. In recent days, Israeli ground troops have been carrying out a raid at Al-Shifa Hospital, searching for evidence that Gaza's militant rulers, Hamas, were using the complex as a command center. The WHO described Al-Shifa Hospital as a "death zone" and urged a full evacuation after leading an assessment mission there on Sunday.

-ABC News' Ayat Al-Tawy, Guy Davies and Morgan Winsor

The Israel Defense Forces and the Israel Securities Authority announced in a joint statement Monday that their troops have killed three more Hamas commanders while continuing ground operations in the Gaza Strip.

"IDF fighter jets, directed by IDF and ISA intelligence, killed three additional Hamas company commanders," the statement read in part. "In addition, IDF troops identified a terrorist cell as they entered a nearby building. As a result of the strike carried out by an IDF aircraft, the terrorists were killed and a weapons depot in which they hid was struck."

There was no immediate confirmation or comment from Hamas.

-ABC News' Dorit Long and Morgan Winsor

Israel Defense Forces troops exposed a 180-foot tunnel 32 feet deep underneath the Shifa Hospital, the IDF and Israel Securities Authority (ISA) said in a joint statement Sunday.

"A deep staircase leads to the entrance of the tunnel shaft, which consists of various defense means including a blast-proof door and a firing hole," the statement continues. "This type of door is used by the Hamas terrorist organization to block Israeli forces from entering the command centers and the underground assets belonging to Hamas. The tunnel shaft was uncovered in the area of the hospital underneath a shed alongside a vehicle containing numerous weapons including RPGs, explosives and Kalashnikov rifles.

"IDF and ISA forces are continuing to uncover the route of the tunnel," the statement adds.

The IDF said it expects to find more tunnels and underground facilities, and that the operation is ongoing and will take some time. About 300 people remain in the hospital, according to the IDF.

-ABC News' Yael Benaya

The World Health Organization confirmed earlier claims by the Palestinian Health Ministry that 31 "very sick" babies were safely transported from Al-Shifa Hospital to another hospital in southern Gaza on Sunday.

The premature infants were evacuated to the Emirates Hospital in Rafah, WHO officials said.

The babies were "clinging to life," the United Nations International Children's Emergency Fund (UNICEF) said in a statement, and their "condition was rapidly deteriorating."

The babies are expected to be transferred to another hospital in Egypt, said Dr. Ashraf al Qwadwa, a spokesperson for the Palestinian Health Ministry. He said nine premature babies have died since the start of a fuel crisis in Gaza prompted by the ongoing conflict.

Six health workers at the Al Shifa Hospital and 10 family members of staff there were also evacuated on Sunday along with the babies, according to the WHO statement, adding that further missions are planned to "urgently transport" the remaining patients and health staff out of the hospital.

-ABC News' Nasser Atta