Some 8.6 million Yemeni children currently lack access to potable water, the UN children’s fund (UNICEF) reported on Thursday.

Speaking via Twitter, UNICEF warned that a chronic lack of access to water and health services was putting Yemeni children at risk of cholera, an infectious — and often fatal — bacterial disease.

According to UN figures, some 85,000 Yemeni children less than five years old have died of malnutrition since the conflict in Yemen began in 2015.

As the conflict enters its fourth year, about 14 million people in Yemen — roughly half of the country’s total population — are at risk of starvation, the UN says.

Read: 85,000 Yemeni children died from malnutrition