Fears are growing that the Islamic State-controlled Taqba dam could collapse, after the jihadists reportedly told nearby residents to evacuate their homes.
Islamic State has claimed the dam, which is situated close to its Syrian stronghold of Raqqa, is on the brink of collapse and released an image of the dam's control room which appears to have been completely destroyed, according to Rudaw.
Isis has also reportedly issued an evacuation order, but this is disputed in some quarters, with some reports claiming militants have in fact been telling local residents to stay in their homes.
The United Nations previously warned that the collapse of the dam could lead to severe flooding, leaving the surrounding area in ruins.
Isis claims American and coalition attacks have left the dam heavily damaged, and made it impossible to perform essential repair work, leaving the facility at crisis point.
US-backed fighters have denied hitting the dam, although the Pentagon believes the barrier is being used as an Isis headquarters to plot attacks outside Syria.
It is also not clear at the moment whether power is still being generated by the dam.