Severe shortages of essential supplies have put millions of young children in Nepal in danger of starving, falling ill or dying this winter, the United Nations Children’s Fund warned Monday.

The organization commonly known as UNICEF issued a news release saying the shortages, caused by political unrest, have imperiled more than 3 million Nepalese kids below the age of 5.

The Associated Press reported protesters upset over the mountainous country’s new constitution have blocked its border with India for months, stalling thousands of supply trucks at the pass.

UNICEF said some government stores are already out of the tuberculosis vaccine and other medicine supplies are at “critically low” levels. The organization also said that some 200,000 families are still living in temporary shelters after being displaced by two major earthquakes in the spring, and those at higher elevations could be particularly at risk during the months ahead.

“The risks of hypothermia and malnutrition, and the shortfall in life-saving medicines and vaccines, could be a potentially deadly combination for children this winter,” UNICEF Executive Director Anthony Lake said in the news release.

Fuel shortages have also put children at risk.

The Associated Press reported that the country’s gas stations are only getting 15 percent of their usual supply of fuel. That’s taken a toll on the country’s ambulances, UNICEF added, which has led to fewer babies being born in hospitals. At least 125,000 births are expected this winter.

With less fuel, UNICEF said more families are relying on firewood to heat their homes. The organization worries that could lead to more indoor pollution and increase cases of pneumonia, which killed 5,000 children under five and sickened some 800,000 more in Nepal last year.