US President Joe Biden said he hoped the temporary truce between Israel and Hamas can go on as long as hostages are being released, after the militant group freed 17 more people, including a 4-year-old Israeli-American girl.

Hamas said it wanted to extend the pause in fighting, which will enter its fourth day and final agreed day on Monday, if serious efforts were made to increase the number of Palestinian detainees released by Israel. Thirty-nine teenage Palestinian prisoners were released by Israel on Sunday, taking the total since the truce began to 117.

Hamas said it had handed over 13 Israelis, three Thais and one with Russian citizenship, and the International Committee of the Red Cross confirmed it had successfully transferred them from Gaza on Sunday.

Biden said the 4-year-old hostage, Abigail Edan, had witnessed her parents being killed by Hamas fighters during their Oct. 7 rampage into Israel and had been held since then.

“What she endured is unthinkable,” Biden said at a news conference in the US.

Abigail was on her way to the hospital for checks, Israel’s Channel 13 said. Her grandfather, Carmel Edan, told Reuters he “simply could not believe” she had been returned, thanking Biden “for all the help he’s offered us.”

The four-day truce agreed last week is the first halt in fighting in the seven weeks since Hamas killed 1,200 people and took about 240 hostages back into Gaza.

In response to that attack, Israel has bombarded the enclave and mounted a ground offensive in the north. Some 14,800 Palestinians have been killed, Gaza health authorities say, and hundreds of thousands displaced.

Israeli Prime Minister Benjamin Netanyahu said on Sunday he spoke to Biden about the hostage release, adding he would welcome extending the temporary truce if it meant that on every additional day 10 captives would be freed.

However, Netanyahu said he also told Biden that, at the end of the truce, “we will return with full force to achieve our goals: The elimination of Hamas, ensuring that Gaza does not return to what it was; and of course the release of all our hostages.”

Palestinians gave the freed prisoners a jubilant reception in Ramallah, according to Palestinian news agency WAFA.

Omar Abdullah Al Hajj, 17, one of the detainees released Sunday, said he’d been kept in the dark about what was happening in the outside world.

“I can’t believe I’m free now but my joy is incomplete because we still have our brothers who remain in prison, and then there is all the news about Gaza that I am having to learn about now,” he told Reuters.

Fragile deal

Sunday’s hostage release follows the liberation of 13 Israelis on Saturday - six of them women and seven of them teenagers or children. Hamas released 24 hostages on Friday, the first day of the truce. A Palestinian source has said up to 100 hostages could ultimately go free.

Qatar, Egypt and the United States are pressing for the truce to be extended beyond Monday but it is not clear whether that will happen.

Clashes and recriminations have threatened to torpedo the existing deal.

The killing of a Palestinian farmer in the central Gaza Strip had earlier added to those concerns. The farmer was killed when targeted by Israeli forces east of Gaza’s Maghazi refugee camp, the Palestinian Red Crescent said.

Violence has also flared in the West Bank, where Israeli forces killed seven Palestinians, including two minors and at least one gunman, late on Saturday and early Sunday, medics and local sources said.

Immense relief

The deal survived an earlier threat when Hamas’ armed wing said on Saturday it was delaying hostage releases until Israel met all truce conditions, including committing to let aid trucks into northern Gaza.

Qatari diplomats are now on site in Gaza to supervise the entry and delivery of their country’s aid, Qatar’s Foreign Ministry said.

A UN official who took part in a humanitarian convoy to northern Gaza said on Sunday aid groups were on track to deliver the biggest shipment in over a month, describing thin, gaunt residents slaking their thirst as soon as water arrived.

“People are so desperate and you can see in adults’ eyes they haven’t eaten,” the UN children’s agency’s James Elder told Reuters by video link from southern Gaza after returning from Gaza City.

Even as the aid deliveries flowed north, Elder said he saw hundreds of Gazans heading in the other direction, fearing the renewal of Israeli bombardments if the four-day truce is not prolonged.

“People are so terrified that this pause won’t be continued,” he said.