The fragile ceasefire between Israel and Hamas appeared to be back on track on Sunday after the release of a second group of militant-held hostages and Palestinians from Israeli prisons, and Egypt said it had received new lists for an expected third release.

Hamas announced that one of its top commanders had been killed, without saying when or how. Israel’s military confirmed this.

The second exchange was delayed for hours Saturday after Hamas accused Israel of violating the agreement, which has brought the first significant pause in seven weeks of war marked by the deadliest Israeli-Palestinian violence in decades and vast destruction and displacement across the Gaza Strip.

Hamas later released 13 Israelis and four Thais, while Israel freed 39 Palestinian prisoners.

Diaa Rashwan, chairperson of the Egyptian State Information Services, said Egypt had received a list of 13 hostages that Hamas was expected to release on Sunday and another list of 39 Palestinians that Israel was expected to free.

White House national security adviser Jake Sullivan told NBC’s “Meet the Press” that the US had “reason to believe” that an American hostage would be released on Sunday and said there were hopes it would be Abigail Edan, the 4-year-old girl who lost her parents in the Hamas attack on October 7.

Sullivan also said that US President Joe Biden would speak to Israeli Prime Minister Benjamin Netanyahu on Sunday.

Separately, Hamas said it had released one of the Russian hostages it was holding, “in response to the efforts of Russian President Vladimir Putin” and as a show of appreciation for Moscow’s position on the war. Israeli army radio had reported that it was an Israeli-Russian dual national.

Hamas and other militant groups seized around 240 people during their rampage across southern Israel that ignited the war. Forty-four have been released, one was freed by Israeli forces and two were found dead inside Gaza.

Meanwhile, Hamas announced the death of Ahmed al-Ghandour, who was in charge of northern Gaza and a member of its top military council. He is the highest-ranking militant known to have been killed in the fighting.

Al-Ghandour, believed to have been about 56 years old, had survived at least three Israeli attempts on his life and was involved in a cross-border attack in 2006 in which Palestinian militants captured an Israeli soldier, according to the Counter Extremism Project, an advocacy group based in Washington.

Hamas said that he was killed along with three other senior militants, including Ayman Siam, who Israel said was in charge of Hamas’s rocket-firing unit.

Agence France-Presse