Syrian rebels ousted pro-government forces from Hama on Thursday, bringing the insurgents a major new victory after a lightning advance across northern Syria and dealing a new blow to President Bashar al-Assad and his Russian and Iranian allies.
The Syrian army said it was redeploying outside the city "to preserve civilians lives and prevent urban combat" after what it called intense clashes.
Rebels said they had taken districts in the city's northeast and had seized the central prison, freeing detainees.
Qatari state-run media Al Jazeera television broadcast what it said were images of rebels inside Hama, some of them meeting civilians near a roundabout while others drove in military vehicles and on mopeds.
The rebels took the main northern city of Aleppo last week and have since pushed south from their enclave in northwest Syria.
Their capture of Hama, which had remained in government hands throughout the civil war triggered by a 2011 rebellion against Assad, will send shockwaves through Damascus and fears of a continued rebel march south.
Hama lies more than a third of the way from Aleppo to Damascus, and its capture would open the road for a rebel advance on Homs, the main central city that functions as a crossroads connecting Syria's most populous regions.
Hama is also critical to the control of two major towns with big minority religious communities - Muhrada, home to many Christians, and Salamiya, where there are many Ismaili Muslims.
Although Hama had not previously been taken by rebels during the war, it was historically a center of opposition to the Assad dynasty's rule.
As his forces swept into Hama the main insurgent commander Abu Mohammed al-Golani issued a video statement warning against any involvement by the other main regional force that is backed by Iran - Iraq's Hashd al-Shaabi militias.
"We urge him (Iraq's prime minister) again to keep Iraq away from entering into the flames of a new war tied to what is happening in Syria," Golani said.
Golani referred to that bloody episode in his statement, saying "the revolutionaries have begun entering the city of Hama to cleanse that wound that has persisted in Syria for 40 years."
What factions are involved?
The most powerful rebel faction is the militant Sunni Islamist Hayat Tahrir al-Sham (HTS), the former al Qaeda affiliate in Syria. Golani, its leader, has pledged to protect Syria's religious minorities and has called on them to abandon Assad, but many remain fearful of the insurgents.
On Wednesday, Golani visited Aleppo's historic citadel, a symbolic moment for rebels who were driven out of the city in 2016 after months of siege and intense fighting, their biggest defeat of the war. Aleppo was Syria's biggest city before the war.
HTS and the other rebel groups are trying to consolidate their rule in Aleppo, bringing it under the administration of the so-called Salvation Government they established in their northwestern enclave.
Conditions in Aleppo
Aleppo residents have said there are shortages of bread and fuel, and that telecoms services have been cut.
The rebel forces advancing on Hama have included a Turkey-backed insurgent coalition called the Syrian National Army, which holds a strip of territory along the Syrian-Turkish frontier, rebel sources said.
Turkey, which designates HTS as a terrorist organization, has long been the biggest external backer of other rebel factions and its role will be critical to the future of any enlarged insurgent region in Syria.
Ankara has denied having taken part in the rebels' sudden sweep into Aleppo last week.