Islamic State fighters have shot dead dozens of young men who tried to flee the western half of Mosul to avoid being press-ganged into the group’s ranks before Iraqi forces launch their final offensive to retake the city.
At least 45 people, the youngest just 16 years old, have been murdered this week, residents said.
ISIS is under increasing pressure in Iraq and Syria after advances by an international coalition and government forces.
Lieutenant General Stephen Townsend, the top US commander in Iraq, said: “Within the next six months I think we’ll see both (the Mosul and Raqqa campaigns) conclude.”
Iraqi forces declared eastern Mosul “fully liberated” in January after launching the operation to retake the city in October, and an assault across the Tigris River on the west of the city is imminent.
Many of the men shot by ISIS were trying to escape being forced to fight as it tries to replenish its ranks after suffering heavy losses in January.
The first mass killing occurred when 40 young men tried to swim from a partially destroyed bridge to government-held territory on the east bank on Monday. Five more were shot dead attempting the same escape on Tuesday.
Abu Muqdad, from the ISIS-controlled al-Shifaa neighbourhood, said four members of his family, including his nephew, had been shot dead.
“ISIS is trying to recruit young men by force,” he said.
“Many young people refused to join ISIS and like my nephew tried to escape. They wanted to swim to safety but they were captured and executed immediately.”
Ali al-Juburi, another resident, said: “Their charge was crossing to the land of infidels”.
The bodies were handed back to the families as a warning.
At least 750,000 civilians are believed to be living on Mosul’s west bank under ISIS control. Many residents, faced with severe shortages of food and medicines and fearful of the looming battle, are desperate to leave.
“Life had become very hard, people are starving and waiting impatiently to get rid of ISIS,’’ said resident Sammi Latif. “ISIS is watching people and trying to find any excuse to punish them.
“They know their days are numbered so they want to kill as many people as possible before they are defeated. The biggest crime for them today is fleeing toward the Iraqi army. The militants have the order to execute people without trial.”
ISIS has also forced people who live near the river to vacate their homes so they can use them as lookouts and strongpoints. The jihadists have been going from house to house, forcing residents to punch holes through their walls to build protected walkways so they can move undetected between buildings.
More than 100,000 soldiers, including Shia militias, elite counter-terrorism squads and Kurdish Peshmerga units, were deployed to retake Mosul, backed by warplanes from the US-led coalition.
The Pentagon said that tests had proven that ISIS had been making rudimentary chemical weapons, including mustard gas, in the recently recaptured Mosul university, which the group used as its headquarters over the past 2½ years. The university was “central to the ISIS chemical weapons program”, said navy captainJeff Davis, a Pentagon spokesman.