Israel rescued four hostages alive from two locations in the heart of Nuseirat, Gaza, Israel said Saturday.

Noa Argamani, 25; Almog Meir Jan, 21; Andrey Kozlov, 27; and Shlomi Ziv, 40, were kidnapped by Hamas from the 'Nova' music festival on Oct. 7, according to the Israel Defense Forces.

The rescues come after a morning of strikes in Central Gaza. Videos show dozens of people in the emergency department at Al Aqsa Martyrs hospital, the region's only functioning hospital.

Hamas called it an "unprecedented brutal attack" and said there are "dozens of martyrs and wounded in the streets" although they do not yet know how many people were killed and injured in the attack.

The rescued hostages have been transferred to the 'Sheba' Tel-HaShomer Medical Center and are in good condition, the IDF said.

-ABC News’ Victoria Beaule

Three Palestinians were killed and 15 others were injured when Israeli forces struck an UNRWA school and shelter in Al-Shati refugee camp in northern Gaza Friday, according to statements from Hamas and the Israel Defense Forces.

Israeli forces said Hamas "terrorists" were operating "from a container inside the grounds" of the school in Al-Shati.

"By targeting this school, which is affiliated with UNRWA, the number of UNRWA schools designated as shelter centers and targeted by the occupation by bombing exceeds more than 150 schools affiliated with UNRWA, in addition to the bombing of dozens of other facilities, installations, and service centers affiliated with UNRWA, which were designated for sheltering displaced people," Hamas said in a statement.

-ABC News' Sami Zayara, Diaa Ostaz and Jordana Miller

After being down for almost two weeks, the temporary pier system has once again been reattached to a beach in Gaza, Vice Admiral Brad Cooper, the deputy commander of U.S. Central Command, told reporters Friday.

"We expect to resume delivery of humanitarian assistance from the sea in the coming days,” Cooper said.

The reattachment to the beach was done by Israeli Defense Force engineers, just as was done the first time when the pier went into operation in mid-May.

During its one week of operations, 1,000 metric tons of aid equal to more than 2 million pounds came into Gaza via the pier, accounting for about 30% of all aid delivered to Gaza that week. With the re-establishment of JLOTS it will become the third route for aid into Gaza right now.

“Given its proven success, we expect to increase the volume of humanitarian assistance provided through the pier over the previous levels,” said Cooper. “We anticipate that our goal will be to deliver 500,000 pounds over the beach initially and then ramp that up soon thereafter. So essentially, essentially every day a million pounds over every two-day period.”

Aid will begin flowing shortly but for now weather conditions are being evaluated to make sure they are appropriate and everything is working properly before aid deliveries are resumed.

-ABC News’ Luis Martinez

At least 40 people were killed -- 14 of whom were children -- and at least 74 others were injured in the Israeli strike on an UNRWA school at the Nuseirat Refugee Camp, the Gaza Ministry of Health said Thursday.

Israeli officials have claimed that the strike was targeting Hamas and Islamic Jihad terrorists "hiding inside the school," IDF spokesman Daniel Hagari said during a press briefing Thursday.

The U.S. State Department said Israelis have claimed they were targeting "only one part of the building without hitting areas where civilians were sheltering," spokesperson Matt Miller said Thursday.

"At the same time, we've seen the reports on the ground. We’ve seen the videos on the ground. We've seen the claims that 14 children were killed in the strike and certainly if ... it is accurate that 14 children were killed, those aren’t terrorists. And so the government of Israel has said that they're going to release more information about this strike, including the names of those who died in it," Miller said. "We expect them to be fully transparent in making that information public."

U.N. Secretary-General Antonio Guterres condemned the strike on the school, which the U.N. said was sheltering some 6,000 internally displaced persons, in a statement.

A spokesperson for Guterres said, "He underscores that UN premises are inviolable, including during armed conflict and must be protected by all parties at all times. The Secretary-General calls on all parties to respect and protect civilians, and ensure their essential needs are met, in accordance with international humanitarian law."

-ABC News' Sami Zayara, Jordana Miller and Shannon Crawford

Israeli forces confirmed the deaths of four more hostages: Haim Peri, Yoram Metzger, Amiram Cooper and Nadav Popplewell.

IDF spokesman Daniel Hagari said the four hostages were "killed together" a "few months ago" while "IDF forces were operating" in Khan Younis in southern Gaza. Hagari said Israeli forces are "examining the circumstances" of their deaths.

Cooper, 85, was an economist and a poet, and a father of four and grandfather of 11, according to Kibbutz Nir Oz. His wife, Nurit Cooper, was also kidnapped and later released, the kibbutz said.

Metzger, 80, was a father of three and grandfather of seven. His wife, Tamar Metzger, was also abducted to Gaza and later released, the kibbutz said.

Popplewell, 51, was kidnapped with his mother, who has been released, the Hostages Families Forum said.

Peri, 80, was abducted while protecting his wife, the Hostages Families Forum said. He leaves behind his wife, five children and 13 grandchildren.

Peri's family said he "heroically survived in the Hamas tunnels, under inhumane conditions, for around 4 months," and he "survived with the hope and faith that the state of Israel will fulfill its moral duty to bring him home."

"The government of Israel and its Prime Minister have no right to leave the hostages in captivity, dismantling Israel’s foundational principle of mutual responsibility," Peri's family said. "We call upon the government of Israel to strive for an immediate deal, save those still alive, and bring those who are not, to a proper burial."

"The heartbreak that comes with this painful news should shake every citizen in the State of Israel and lead every leader to profound soul-searching," the Hostages Families Forum said in a statement Monday. "The Israeli government must send out a negotiating delegation this evening and return all 124 hostages, both living and murdered. ... We reiterate our demand to the Israeli government: approve the Netanyahu deal immediately!"