Hundreds of patients are trapped inside another major hospital in the Gaza Strip amid fierce fighting between Israeli forces and Hamas militants, as fears grow that the situation could turn into a repeat of what happened at Al-Shifa Hospital.

The Indonesian Hospital is located in the northern edge of north Gaza, right on the frontline of Israel's advance. Al Jazeera reported that there are 700 people currently stuck inside the besieged hospital, including medical staff and wounded civilians.

At least 12 people, including patients and their companions, were reportedly killed on Monday when the Indonesian Hospital came under fire, according to the World Health Organization, which said it was "appalled by the attack." Doctors in the hospital told Al Jazeera that the facility was hit by artillery shells, while others suggested an Israeli tank may have fired at it.

"Health workers and civilians should never have to be exposed to such horror, and especially while inside a hospital," WHO Director-General Tedros Adhanom Ghebreyesus wrote in a post on X, the social media platform formerly known as Twitter.

Dr. Marwan Al-Sultan, director of the Indonesian Hospital, told BBC News that Israeli troops were only about 20 meters (66 feet) away. The Israeli military said its forces targeted "terrorists" who had opened fire at them from within the hospital, according to BBC News.

ABC News has not confirmed that Israeli troops were responsible for strikes on the Indonesian Hospital. The Israel Defense Forces said it was operating in specific areas outside the hospital due to enemy fire and that no shells were launched toward the facility.

Gaza's Hamas-controlled Ministry of Health said 200 patients were evacuated from the Indonesian Hospital by bus to southern Gaza and that the International Committee of the Red Cross was trying to coordinate the evacuation of the remaining 400 patients, according to BBC News.

Video purportedly taken inside the Indonesian Hospital shows injured people and others sheltering on the floor. Additional footage appears to show damage to the hospital and heavy bombardments landing close to the facility in recent days.

-ABC News' Patrick Reevell, Kerem Inal and Morgan Winsor

A little more than 1,200 Americans and their eligible family members are waiting to leave Gaza, according to State Department spokesperson Matt Miller.

About 800 Americans and eligible family members have already left Gaza, Miller said.

Since the Israel-Hamas war broke out on Oct. 7, another six Americans have died: one was an Israeli national police border officer and five were members of the Israel Defense Forces, Miller said. At least 33 Americans were killed in Israel on Oct. 7 during Hamas' attack, according to American officials.

-ABC News' Shannon Crawford

President Joe Biden said Monday he thinks negotiators are close to reaching a deal to release hostages from Gaza.

When asked at the White House turkey pardon if a deal is near, Biden responded, "I believe so, but I’m not prepared to talk to …"

"You believe so?" reporters followed up, cutting off Biden's initial comment. Biden replied, "Yes," before holding up crossed fingers.

National Security Council spokesman John Kirby told reporters Monday, "We believe we’re closer than we’ve ever been, so we’re hopeful. But there’s still work to be done, and nothing is done until it's all done, so we’re gonna keep working on this."

Kirby wouldn't say if the deal was focused on securing the release of women and children and wouldn't discuss a potential timeframe the administration was looking at for a deal to be announced.

"I think the less said the better as we get into ... what we hope is the end game here on negotiations. It's probably safer if I don’t go into much speculating," Kirby said.

-ABC News' Molly Nagle

While southern Gaza is deemed safer than northern Gaza, Israel will be operating in southern Gaza soon, according to an Israeli official.

The official said operations in southern Gaza will be more "targeted."

The official said the actual "safe" zone would be in the sparsely populated Muwassi area in southwest Gaza.

But the official said Israeli forces would still strike there if need be.

Hamas announced that it will be delaying the release of Israeli hostages, accusing Israel of violating the cease-fire agreement regarding aid trucks and the agreed-upon terms for the release of Palestinians imprisoned in Israel.

The Al-Qassam Brigades -- the armed wing of Hamas -- said it had decided to delay Saturday's scheduled second round of hostage releases until Israel committed to allowing aid trucks to enter northern Gaza. Hamas was expected to release 13 Israeli hostages in exchange for the release of 39 Palestinians imprisoned in Israel on Saturday, sources told ABC News.

"The Al-Qassam Brigades decides to delay the release of the second batch of hostages until the occupation adheres to the terms of the agreement regarding the entry of relief trucks into the northern Gaza Strip, and due to its failure to adhere to the agreed-upon criteria for releasing prisoners," Al-Qassam Brigades said in a statement.

Hamas leader Osama Hamdan, who is based in Lebanon, said relief trucks that arrived in northern Gaza today were half of the number that was agreed upon.

"There are violations committed by the Israelis in implementing the terms of the truce, some of which occurred yesterday and were repeated today," Hamdan said Saturday, adding that another issue at stake was the reported shooting of two Palestinians on Friday as they tried to reach northern Gaza.

A senior Israeli political source told ABC News that Israel did not violate the agreement. The IDF said about 200 trucks carrying humanitarian aid are expected to enter Gaza today, after 200 trucks with aid entered Gaza yesterday via the Rafah crossing and delivered their cargo to international aid organizations.

The Palestinian Red Crescent said 61 trucks carrying food, water and medical supplies headed to northern Gaza on Saturday, the largest aid convoy to reach the area since the start of the war.

-ABC News' Ayat Al-Tawy, Nasser Atta, Jordana Miller