The Iraqi managed to herd around 40 members of his extended family out of the neighbourhood of Samah "by advancing quietly, hiding under stairs, sidling along walls".
On Saturday, he and his relatives were receiving assistance at a camp in Khazir, a Kurdish-controlled area further east, where displaced civilians are arriving in growing numbers.
Most are from Mosul's outskirts, but Abu Fahad and a few others were able to find a gap in the tight seal the Islamic State group had imposed on the city.
Two weeks after Iraq launched its largest military operation in years to retake Mosul, the last major Iraqi hub in the jihadists' shrinking "caliphate", forces reached the edge of the city.
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Now the million-plus people believed to be trapped inside have to survive fire from both sides to flee the brutality of the jihadists who have ruled them for more than two years.
Abu Sara fled the same neighbourhood, dodging gunfire, bombs, mortar rounds and strikes from the US-led coalition, such was his desperation to leave what many civilians who escaped IS rule describe as an open-air prison.
"There were snipers shooting, mortars crashing down, it was hell," said the 34-year-old, wearing a brown fake leather jacket.
"We walked several miles, taking with us only the clothes we were wearing and white flags we waved the entire way."
Sitting next to him and stroking her belly, his pregnant cousin Umm Mustafa said she could hardly believe she had finally escaped her life spent "hiding under niqab" face veils.
'Coming back to life'
Despite the cold filling the tent that is their new home in Khazir, she was all smiles and wore a teal-coloured dress with matching scarf.
"We're coming back to life," said Umm Mustafa, keeping a watchful eye on some of her seven children as they played in the gravel at her feet.
Abu Ahmed also said that "life had stopped" for many of the million-plus people who remained in Mosul after IS proclaimed its "caliphate" in June 2014.
"All the factories stopped working, there was no work and no money," said the 60-year-old man, who worked in the oil sector before the jihadists took over.
Sitting next to water taps at the intersection of four of the camp's alleys, Abu Ahmed said he hadn't initially planned to flee Mosul and his neighbourhood of Al-Khadra.
He recounted the night that he and his wife were having dinner at their children's place in the Samah neighbourhood.
"We stayed in their home because the bombing was just too intense to go out, but then we escaped and I found myself here," he said. "We left everything behind, we have only God."
Abu Fahad, his wife and six children also fled with none of their belongings but they are safe, unlike some of their relatives who remained trapped in Mosul.
"I still have two sisters in the Al-Karama neighbourhood... and I have absolutely no news," she said.
Al-Karama is one of the first districts that the elite Counter-Terrorism Service entered on Friday.
The force's commanders said they encountered fierce resistance there and intense fighting was still ongoing on Saturday.
"There's no phone network there, the only place where you might get a signal is on roofs but there are snipers up there," said Abu Fahad.
He said he had heard from neighbours who escaped after him that five residents of the area were killed trying to flee.
