Ido Dan, a relative of Israelis Sahar Calderon, 16, and Erez Calderon, 12, spoke of the joy at their release on Monday mixed with anxiety about their father, Ofer, who is still being held.

“It is difficult to go from a state of endless anxiety about their fate to a state of relief and joy,” Reuters quoted Dan as saying. “This is an exciting and heart-filling moment but … it is the beginning of a difficult rehabilitation process for Sahar and Erez, who are still young and have been through an unbearable experience.”

Israel previously said it would extend the truce by one day for every 10 more hostages released, providing some respite to Palestinians in the Mediterranean seaside strip from the fighting.

Israel has not commented on any agreement to extend the truce but, in what may be an implicit confirmation, the Israeli prime minister’s office said Israel’s government approved the addition of 50 female prisoners to its list of Palestinians for potential release if additional Israeli hostages are freed.