Some troops had been expected to withdraw to allow hundreds of thousands of displaced Gazans to go home. But the military said the hostage exchange before that step had not gone as agreed.

All four hostages are female Israeli soldiers. They are expected to be released Saturday in accordance with a ceasefire agreement with Israel that's halted fighting in the Gaza war since last weekend.

Israeli troops have pulled back to the edges of Gaza, the first hostages have been released and many Palestinians have returned to what remains of their homes in the first few days of the Israel-Hamas ceasefire deal.