The civilian, Arbel Yehud, should have been among the first two groups of hostages released on Jan. 19 and Jan. 25 under the cease-fire deal, according to the Israeli authorities.

Tens of thousands of Palestinians began returning to a ravaged northern Gaza and what was left of their homes and families, after Hamas agreed to release more hostages than expected this week to keep its cease-fire with Israel in place.

After four female Israeli soldiers were released by Hamas over the weekend, six more hostages were to be released this week. Some of those expected to be freed in the first phase of the ceasefire with Israel are thought to be dead.