A second group of Israeli hostages and foreign nationals were handed over to the Red Cross on Saturday and brought out of Gaza into Egypt after hours of delay.

Hamas, the militant group that governs the Gaza Strip, confirmed the release of 13 Israeli hostages in a Telegram text. The Israeli military said it was informed those freed included four Thai nationals.

The transfer of the hostages is the first stage in the second day of exchanges between Israel and Hamas, and is part of an agreement that involves a four-day cessation of fighting and a flow of more humanitarian aid into Gaza.

Earlier Saturday, Hamas delayed the release of the hostages, saying Israel had violated the terms of the truce. Israel denied the accusation.

The last-minute snag underscored the fragility of the truce and deep distrust between Hamas and Israel. Hamas militants infiltrated Israel on Oct. 7, killing 1,200 people and abducting about 240 hostages. Their recovery has become an urgent priority for Prime Minister Benjamin Netanyahu’s shaky government.

Israel has unleashed its military might on the small, crowded Gaza Strip after the attack. At least 15,000 people have been killed, according to the health ministry run by Hamas, which the US and the European Union have designated a terrorist group.

US President Joe Biden earlier Saturday spoke with Qatari leaders “on potential holdups to the deal and mechanisms to resolve them,” said Adrienne Watson, a spokeswoman for the National Security Council. Qatar has been the main negotiator in efforts to release the hostages.

After weeks of negotiations, the two sides this week agreed to a limited truce, contingent on Hamas releasing a total of 50 hostages and Israel freeing 150 women and minors held in the nation’s prisons.

The first exchange on Friday went as planned: Hamas released 13 Israelis, some with dual citizenship and all women and minors. In a separate deal, it also released 10 Thai nationals and a citizen of the Philippines.

Israel then freed a first group of 39 jailed Palestinians.

Biden, who said the first day had “gone well,” was kept informed of developments Saturday and, after his call with the Qatari leaders, senior US officials were in “regular contact with the Israelis, Qataris, and Egyptians to overcome hurdles,” Watson said.

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