The Israeli military says it has partially withdrawn troops from parts of Gaza after a ceasefire agreement between Israel and Hamas came into effect on Friday morning.
Israeli forces said they had pulled back to an agreed position within the territory - though troops still occupy half of the Strip.
Footage shows thousands of Palestinians making their way to the north of Gaza, which has been heavily bombarded by Israeli forces in recent months.
The ceasefire came into effect after the Israeli government approved the first phase of US President Donald Trump's ceasefire and hostage return deal on Thursday. The next phases are still being negotiated.
Under the deal, Hamas has until 12:00 local time (10:00 BST) on Monday to release all Israeli hostages - including 20 who are believed to be alive, and up to 28 hostages' remains.
Israel should also release about 250 Palestinian prisoners serving life sentences in Israeli jails. Israeli army radio said 100 will be released into the West Bank and five to East Jerusalem. More are expected to be deported.
A further 1,700 Palestinians from Gaza who have been detained should also be released.
Under the terms of the deal, aid trucks should also be allowed unrestricted into the Strip to bring desperately needed aid to Gaza's population - many of whom have been repeatedly displaced during the two-year war.
A famine was declared in part of the territory for the first time in August by UN-backed experts, who said more than half a million people were facing catastrophic conditions characterized by starvation, destitution and death. Israel has repeatedly denied that there is starvation in the territory.
Eyewitnesses in Gaza said troops had pulled back from the north-western outskirts of Gaza City towards the east.
In the south, some Israeli troops were also reported to have pulled back from the Khan Younis area.
Israeli Prime Minister Benjamin Netanyahu said in a televised address he was fulfilling the promise to bring back all the hostages.
In areas of Gaza City where the IDF had withdrawn, Hamas security forces were deployed on the streets. They were pictured wearing caps with the logo of the Hamas Internal Security agency rather than a regular police force.
As troops partially withdrew, thousands of Palestinians were filmed travelling - many on foot - up Gaza's coastal road to the north.
Many were travelling on foot for more than 20km (12 miles) carrying what remained of their belongings on their backs.
The road is long and difficult, there's no food or water, said Alaa Saleh, a schoolteacher who fled Gaza City with his wife and six children to Khan Younis in the south.
Videos circulating online show vast swathes of destruction in the city's main neighborhoods. Gaza's civil defense crews have been recovering bodies from beneath the ruins, while aid agencies have warned that essential supplies like food, fuel, and clean water remain critically scarce.