Hamas released six Israeli hostages from Gaza on Saturday, delivering the last living captives set to be freed in the first phase of a fragile cease-fire. Early Sunday, Israel announced that it would continue to delay the release of 620 Palestinian prisoners whom it had pledged to free on Saturday, demanding that Hamas first release more captives from Gaza and commit to releasing them without 'humiliation ceremonies.' The announcement added tension to the shaky cease-fire between Israel and Hamas that is set to expire next week.