BEIRUT (Reuters) - As Syrian government forces advanced into Aleppo's rebel-held al-Sakhour district, Hasan al-Ali said he faced the choice of staying put and being caught by the army, or fleeing into a shrinking rebel enclave under relentless bombardment.
A father of three children, he opted for the latter, though food, fuel, water and medicine are running critically low in rebel-held areas, such is his fear of the Syrian government that insurgents have been trying to unseat for more than five years.
"I didn't take anything with me. I took the kids, ran to my car, and left... We took the decision at the final hour, because the army could have swooped in at any moment," the 33-year-old said, speaking in eastern Aleppo.
For Ali and thousands of others in the areas that fell to the army in recent days, the danger and deprivation of east Aleppo seem a safer bet than the imprisonment or enlistment into the military that they fear if they moved to government areas.
But as some fled deeper into Aleppo's remaining rebel districts, others decided instead to risk a perilous crossing of the front lines into government-held parts of the city, seeing it as a safer option than staying with the outgunned rebels.
"I hope Syria will return to the way it was, and people get back security and peace like before," said Abed al-Salam Ahmad, who crossed to the government sector with his wife and six daughters after their house was hit by a shell.
The former construction worker said conditions were so bad that even animals would not endure them, and that inhabitants were badly treated by east Aleppo's rebels - something the rebels deny. His family fled at dawn, braving gunfire as they crossed the front line.
He spoke to Reuters TV at a disused cotton factory in Aleppo's Jibreen area, one of two former industrial facilities opened by the government to receive the displaced.
The divergent paths chosen by Ali and Ahmad illustrate the terrifying choices that have faced civilians fleeing one of the most ferocious battles of the Syrian war, with President Bashar al-Assad poised for his biggest triumph of the conflict so far.
Both the rebels and the government have accused each other of manipulating Aleppo residents' fears to their own advantage.
The military say rebels spread false reports of government abuses to deter people from leaving rebel areas. Rebels in turn say that people who speak of mistreatment by insurgents after fleeing their territory are acting out of fear of authorities.
Since the army swept through the northern part of the rebel enclave a week ago, capturing several large, populous districts, at least 30,000 people have fled across the front lines from the rebel areas, the U.N.'s relief coordinator OCHA said.
Thousands of others - the numbers are more difficult to calculate because international bodies are not present in rebel-held east Aleppo - retreated further into the insurgents' sector, including to the dense quarters of the Old City. OCHA estimates 5,000 had been displaced within eastern Aleppo.
The U.N. envoy for Syria said on Saturday there may still be more than 100,000 people in rebel-held areas. The Britain-based Syrian Observatory for Human Rights said it could be as many as 200,000.
For those remaining in districts held by rebels, conditions are worsening, aggravated by the shortage of basic goods and the constant danger of bombardment in civilian areas and fighting near the quickly shifting front lines.
"We had a lot of starvation. They were giving us every day or two days a bag of bread, so five loaves of pitta bread," said a woman who gave the name of Um Ali, or 'Ali's mother', who had fled to the government sector from her home in Jeb al-Qubba district.
After the army has finished checking the identity papers of her and her family, she hopes they can move in with her brother in a western district of Aleppo that is in government hands.
Many of those who chose to remain in rebel areas believe that checks of identity papers are a prelude to mass arrests, torture and extrajudicial killing, citing previous media reports of such action - all dismissed by Damascus as fabricated.
The Observatory said on Wednesday the government had detained hundreds of people. A Syrian military source denied that, and said that while identities were being checked, nobody was being arrested.
Khalil Halabi, 35, a pharmacist from al-Shaar district near the new front line, moved with his wife and children to the rebel-held Old City after what he described as 11 days of escalating bombardment.
"The destruction is indescribable - the limbs, burnt limbs. Buildings collapsed and were burned down, mosques were destroyed completely," he said.
"We lost a lot of people... through barrel bombs and rockets. Some of them died and some of them were permanently injured," he said. Others from his district fled in the other direction, seeking shelter in government areas.
For the people Reuters spoke to in Aleppo, the decision to leave home, even in the face of such deprivation and after a war that began in Syria in 2011 and arrived in their city in 2012, came as a wrench.
Mahmoud Zakaria Rannan, a tailor from the city's Sheikh Najjar neighborhood who has six children and owned a small shop, said his family finally decided to leave after he was wounded when their house was shelled.
"I had been in my home for 40 years, was I going to leave it in one day?" he said. The family went to the Sheikh Khudr district and then to the Old City. But as clashes continued, they decided to join his brother in government-held Adamiya.
"We have kids, and I'm injured... so we had to walk very slowly," he said. His journey included a two-hour trek through the city starting at 4 am. "There was a big group with us. They even fired on us at the airport highway."
Some of those trapped inside the rebel sector may still be hoping to escape through a deal between rebels and the government, such as those that allowed thousands to leave Daraya near Damascus for insurgent-held Idlib after years of siege.
"I will go to another area, I'll take my family and seek refuge in another area, a liberated area that doesn't have the regime. I have no trust at all in the regime to stay in its areas," said Ali.
Reporting by a multimedia team in western Aleppo and stringer in eastern Aleppo,; Writing by Ellen Francis and Angus McDowall; Editing by Tom Perry and Dominic Evans