A temporary ceasefire and the release of dozens of prisoners taken by the Palestinian armed group Hamas in its Oct. 7 attack on Israel will not come into effect until Friday, Tel Aviv said, as Israeli forces continued to bombard the besieged Gaza enclave.

The publication is part of one temporary ceasefireIsrael and Hamas agreed on Wednesday that the operation, originally scheduled to last four days, would also include sending urgently needed humanitarian aid to Gaza.

The prisoners are to be exchanged for a number of Palestinians held in Israeli prisons.

“Negotiations for the release of our hostages are progressing and ongoing,” Israeli National Security Adviser Tzachi Hanegbi said in a statement released by the Prime Minister’s Office.

“The start of publication will take place in accordance with the original agreement between the parties and not before Friday,” it said.

Israeli public broadcaster Kan reported, citing an unidentified Israeli official, that there was a 24-hour delay because the agreement was not signed by Hamas and Qatar, the deal’s main broker. The official said they were optimistic that the agreement would be implemented as it was signed.

“Nobody said there would be a release tomorrow except the media… We had to make it clear that there is no release planned before Friday because the families of the hostages are facing uncertainty,” Kan quoted an unnamed source from Israeli Prime Minister Benjamin Netanyahu as saying office said.

Other Israeli media published similar reports, quoting anonymous officials, saying the lull in fighting with Hamas would not begin until Friday.

Since Israel’s inception, more than 14,500 people have been killed in Gaza attacks in the territory in response to Hamas’ attack on Israel that killed at least 1,200 people.

About 240 people have been arrested by Hamas militants, but only four have been released so far.

Before October 7, there were about 5,200 Palestinians in Israeli prisons, although that number is already over 5,200 doubled according to the Palestinian authorities in the following weeks.

Amid the apparent delay in the ceasefire agreement, Israeli aircraft and artillery attacked the southern Gaza town of Khan Younis in at least two waves early Thursday.

In Israel, sirens wailed in communities near the border with the enclave, warning of rocket fire from Gaza, the military said. There were no reports of damage or injuries.

Tensions also rose along Israel’s northern border early Thursday after the Iran-backed Hezbollah group said five of its fighters, including the son of a senior lawmaker, were killed.

Meanwhile, in the Red Sea, U.S. Central Command said the USS Thomas Hudner shot down “multiple disposable attack drones launched from Houthi-controlled areas in Yemen,” referring to another Iranian-backed group.

“I want everyone back”

The delay caused frustration for families on both sides.

Under the terms of the agreement, 50 Hamas prisoners are to be released, with at least 10 released each day.

“We don’t know who is coming out because Hamas will publish every evening the names of those who come out the next day,” said Gilad Korngold, who was still waiting for word from his relatives. Seven of his family members, including his three-year-old granddaughter, were kidnapped by Hamas.

“I want everyone back. But I think – and it’s a very difficult decision – but I think it has to be the children and women [first]. They are the most fragile. You know, they have to get out.”

Netanyahu’s office explained this armistice could be extended as long as another 10 hostages were released each day.

Israel’s list of 300 eligible Palestinian prisoners, including 123 children and 33 women, includes Shorouq Dwayyat, who is serving a 16-year sentence for attempted murder in a 2015 knife attack. Activists say she is one of many Palestinians who have been wrongly tried and convicted on unfair or trumped-up charges.

“I was hoping she would make a deal,” her mother said. Sameera Dwayatsaid, but added that her relief was tempered by “great pain in my heart” over the dead children in Gaza.

The U.S. also hoped aid would reach Gaza in large quantities in the coming days, White House national security spokesman John Kirby said.

Hamas said The first 50 prisoners would be released in exchange for 150 Palestinian women and children imprisoned in Israel. Hundreds of trucks carrying humanitarian, medical and fuel supplies would enter the Gaza Strip, while Israel would suspend all air operations over the southern Gaza Strip and maintain a six-hour daily no-fly window in the north, it said.

The ceasefire agreement, the first in a nearly seven-week war, was reached after mediation by Qatar and is seen by governments around the world as potentially alleviating suffering in the Gaza Strip, home to more than two million people.

In a statement shared by US media, National Security Council spokesperson Adrienne Watson stressed that the agreement “has been agreed and remains agreed.”

“The parties are working out the final logistical details, particularly for the first day of implementation,” CBS News and CNN Watson reported.

“We believe that nothing should be left to chance when the hostages come home. Our primary goal is to ensure they are brought home safely. This is on the right track and we hope that implementation will begin on Friday morning.”