Israel-Gaza updates: IDF says it exposed Hamas tunnel under Shifa Hospital

National Security Council spokesperson John Kirby on Wednesday denied that the U.S. gave any "OK" for the Israeli operation at Gaza's Al-Shifa Hospital.

"These are Israeli military operations that they plan and they execute on, you know, in accordance with their own established procedures, that the United States is not, was not, involved in," Kirby said.

He also denied that the U.S. confirming intelligence that Hamas uses the hospital as a control center had anything to do with the timing of the Israeli military operation at the hospital, which began only hours after Kirby's announcement.

Kirby also said Israel's hospital operation was "not a focus" of President Joe Biden's Tuesday night conversation with Israeli Prime Minister Benjamin Netanyahu and would not say if the U.S. got a heads up about the operation.

"Again, we don't expect the Israelis to advise us or inform us when they are going to conduct operations," Kirby said. "We talked to them routinely every day, and certainly we talked to them about our continued concerns over civilian casualties and sharing our perspectives on the best way to minimize, but these are their operations."

-ABC News' Sarah Kolinovsky

As Israeli ground forces continue to carry out an hourslong raid on the largest hospital in the Gaza Strip on Wednesday, staff there told ABC News that none of the patients have been moved out.

There are about 600 patients admitted to Al-Shifa Hospital in Gaza City, many of whom are seriously ill or wounded. Thousands of other people have been sheltering in the vast medical complex amid Israel's bombardment of the area.

Speaking to ABC News via telephone from inside the hospital, Dr. Ahmed Mokhallalati described the moment Israeli troops arrived at the complex before dawn on Wednesday.

"They told us no one should look through the windows," said Mokhallalati, who is the head of the hospital's plastic surgery department.

"The whole situation is really horrible," he added. "They are just scaring everyone here."

-ABC News' Dragana Jovanovic

A senior Israeli defense official said Wednesday that so far Israeli troops have not engaged in combat inside Al-Shifa Hospital itself and suggested they have not yet encountered Hamas fighters within the vast medical complex, the largest in the Gaza Strip.

However, the Israel Defense Forces' ground operation at Al-Shifa Hospital in Gaza City is ongoing and they have allegedly found evidence -- specifically weapons -- that Hamas, the militant group that rules the strip, is operating inside there, according to the official. More details will be revealed later Wednesday, the official said.

Hamas has since released a statement calling Israel's claim that it found weapons inside Al-Shifa Hospital "a blatant lie."

The senior Israeli defense official told reporters that Israeli soldiers went into Al-Shifa Hospital to destroy Hamas infrastructure, not to go after Hamas leaders.

The official noted that four Hamas fighters were killed near the medical complex as Israeli troops approached, but said they are still investigating if they came from inside the hospital.

The official said Israeli forces are currently operating only in "one area" of the hospital but warned that they will enter other areas as needed. The IDF has "no intention" of sending its soldiers to fight "among the patients or the active personnel of the hospital," according to the official.

The official told reporters that the hospital's youngest patients -- dozens of premature babies -- are in a building of the complex not where Israeli troops are currently operating. Israeli soldiers delivered incubators and baby food at the front gate of the hospital in hopes that the staff there would take them, according to the official.

The official declined to say where exactly Israeli forces were operating within the complex, citing operational security.

Al-Shifa Hospital was designed by Israeli architects decades ago and the IDF knows its layout well.

-ABC News' Jordana Miller, Patrick Reevell and Joe Simonetti

The head of the United Nations' humanitarian relief operations condemned on Wednesday the Israeli military’s ongoing raid on the Gaza Strip's largest hospital, saying he is “appalled” by the reports of the operations.

"I'm appalled by reports of military raids in Al Shifa hospital in #Gaza. The protection of newborns, patients, medical staff and all civilians must override all other concerns. Hospitals are not battlegrounds," U.N. Under-Secretary-General for Humanitarian Affairs and Emergency Relief Coordinator Martin Griffiths wrote in a post on X, the social media platform formerly known as Twitter.

-ABC News' Patrick Reevell