Hamas said a group of hostages seized were handed over on Friday as a temporary truce took hold in Gaza following weeks of fighting.
"The prisoners were handed to the Red Cross who will take them to the Egyptians" at the Rafah crossing, a source close to Hamas told AFP.
A source in the military wing of Hamas confirmed the handover, adding: "This is the first group under the agreement."
A first tranche of 13 women and child hostages were expected to go back to Israel on Friday under a deal that followed weeks of talks involving Israel, Hamas, Qatar, Egypt and the United States.
Israel is set to release three times as many Palestinian prisoners from Israeli jails -- women and teenage boys.
A dozen Thai hostages kidnapped during Hamas's October 7 campaign into Israel were also released on Friday, Thailand's Prime Minister Srettha Thavisin announced.
Pictures released by the Israeli army showed bright pink and blue headphones sitting on the seats of a helicopter ready for the released hostages to use, along with toys and teddy bears waiting at a reception centre where they were being taken to.
During a four-day truce, at least 50 hostages are expected to be freed, leaving an estimated 190 in the hands of Palestinian militants.
In exchange, 150 Palestinians prisoners are expected to be released.
The pause in fighting triggered a mass movement of thousands of Gazans who had sought refuge in schools and hospitals from relentless Israeli bombardment.
In Khan Yunis, in southern Gaza where many Palestinians fled, a cacophony of car horns and ambulance sirens has replaced the sound of war.
For Khaled al-Halabi, the truce is "a chance to breathe" after nearly seven weeks of war.
Israel's air, artillery and naval strikes alongside a ground offensive have killed about 15,000 people.
Gazans have struggled to survive with shortages of water and other essentials. Trucks carrying more aid, including fuel, gas, and food, began moving into Gaza from the Rafah crossing with Egypt shortly after the truce began at 7am.
Jens Laerke, spokesman for the United Nations humanitarian agency, OCHA, expressed hope in Geneva that the pause "leads to a longer-term humanitarian ceasefire for the benefit of the people of Gaza, Israel and beyond."
He repeated the need for access across Gaza, especially in the north "where the damage and the humanitarian needs are the greatest".
According to the UN, 1.7 million of Gaza's 2.4 million people are estimated to have been displaced by the fighting.
Israeli warplanes dropped leaflets warning people that the war is not over and it is "very dangerous" to return north, the focus of Israel's military campaign.
The truce was also a chance for some Palestinians to return to Gaza through the Rafah crossing.
In the morning, a few apparent gunshots could be heard and dark plumes of smoke rose periodically over northern Gaza, an AFPTV livecam showed, but the truce appeared to be holding in the afternoon.
Further north, on the Lebanon-Israel border, calm also returned after regular deadly exchanges of fire, primarily between the Israeli army and Hezbollah. The Lebanese movement, like Hamas, is backed by Iran.