At least 15 children have died in Syria because of a lack of medical care and inadequate living conditions for displaced people amid freezing temperatures, the UN has said, warning that more deaths are likely to follow.

Eight babies in the Rukban camp on the Jordanian border had died from hypothermia in the last month, a statement from the UN children’s fund said on Tuesday. A further seven children, mostly under one year old, had died from the cold in recent weeks as their families fled the battle for Hajin, one of the last areas held by Islamic State in eastern Syria.

“Extreme cold and the lack of medical care, for mothers before and during birth and for new infants, have exacerbated already dire conditions for children and their families,” said Geert Cappelaere, Unicef’s regional director.

“The lives of babies continue to be cut short by health conditions that are preventable or treatable. There are no excuses for this in the 21st century. This tragic man-made loss of life must end now.”

The freezing winter weather has piled pressure on the already inadequate infrastructure for the estimated 6 million Syrians who have been displaced within the country’s borders over the last eight years of civil war, and for the estimated 4 million living in neighbouring Jordan, Lebanon and Turkey. At least 22,000 refugees in Lebanon have lost tents and belongings in recent storms and snowfall that have flooded hundreds of informal camps.

Forecasts indicate the cold snap is set to worsen, bringing more snow, strong winds and plunging temperatures.

People in Rukban camp in particular have suffered. Although home to 50,000 people, 80% of whom are women and children, the area in the demilitarised zone between Syria and Jordan has fallen victim to the struggle for control of the border, becoming cut off from doctors and aid shipments.

No aid supplies have reached Rukban since November, forcing residents to rely on smugglers for food and medicine. In 2018 at least 12 people died of malnutrition and complications arising from a lack of appropriate medical care.

UN agencies and workers at the camp have denied reports this week that a female resident unable to feed her three children set her family and herself alight in an act of desperation. All four are in a stable condition and being treated for second-degree burns at a hospital in Jordan. Administrators said the injuries were caused by a cooking stove fire.

Mahmood al-Hamil, who works at the camp, said the incident was an accident but he believed many of Rukban’s residents were desperate.

“I believe if we receive no help, especially in this cold winter, we will witness suicide attempts – people are so hopeless and desperate here,” he said. “Rukban camp is a death camp with all roads blocked.”

Fighting between rebel factions and an al-Qaida affiliate in Idlib province, as well as the prospect of a Turkish military operation against Kurdish forces in Syria’s north-east, have raised fears of further mass displacements.

“Without reliable and accessible healthcare, protection and shelter, more children will die day in, day out in Rukban, Deir ez-Zor and elsewhere in Syria. History will judge us for these entirely avoidable deaths,” Cappelaere said.