Separated from her family in the scramble to board a boat, an Iraqi woman has narrated her horrific story as she helplessly watched her two grandchildren drown in a river as they tried to flee from ISIS-held Fallujah.

Forced to eat rotten dates and drink contaminated river water as all supply routes have been cut off, Nuriya was among many who tried to flee as the Iraqi city turned into hell on earth.

"People jumped from the other side of the river and saved some of those who were drowning, but not my son’s two girls and his boy," said the 50-year refugee.

Two of her sons - one of them the father of the three children - were unable to cross and she has since lost contact with them.

We’ve heard stories of starving mothers drowning themselves with their babies in the river

She recounted her story to Karl Schembri, a Maltese aid worker with Norwegian Refugee Council yesterday.

Around 50,000 civilians are trapped inside the ISIS stronghold as Iraqi forces and allied militias prepare to storm the city.

Mr Schembri stumbled upon Nuriya as he was filming inside the displacement camp in Amariyat Al Fallujah. 

"I could see how torn she was, having fled from the shelling, the fighting and extreme hunger, while having to turn down her son’s demand to go back to the other side of the river under ISIS control, while witnessing the drowning of her little grandchildren."

Just like Nuriya, thousands of others are forced to make desperate choices to flee from Fallujah, currently under attack and under ISIS control.

"We’ve heard stories of starving mothers drowning themselves with their babies in the river, and others who were frail and unable to leave who gave away their children to fleeing relatives so they could take them to safety. We have been unable to reach the civilians of Fallujah in months and now they are risking their lives to reach our camps."

Nuriya and her family escaped 10 days ago under cover of darkness until they reached the river bank. They stayed there for two days without food until they managed to cross with other people. But it was total chaos.

Aid worker Karl Schembri.

"When the boat I was on reached the middle of the river I heard a lot of screams, another boat was sinking. People were shouting, 'save us, save us'. People jumped from the other side of the river and saved some of those who were drowning, but not my son's two girls. Their mother was holding on to two of them; one of them was still alive, the other one was already dead, until she lost them. We couldn’t see the girls, we only found their bodies later far away near Bzeibez Bridge," she said. 

Nuriya's son frantically told the rest of his family to return.

"I couldn't. I couldn’t even return his dead children to him. If we went we'd die of hunger, mortars and shelling. His poor children drowned hungry. They hadn’t eaten in two days.

“My son remained there, he couldn’t cross, together with another son of mine. Now I’ve lost contact with them. I don’t know what happened to them, but I can’t go back to them.”

The Norwegian Refugee Council is working day and night to receive newly-displaced civilians and providing them with emergency aid.