Mariupol residents have become so desperate that some have fought each other for food during Russia's siege of the Ukrainian city, the International Committee of the Red Cross said Thursday.
"People started to attack each other for food. People started to ruin someone's car to take the gasoline out," said Mariupol-based ICRC representative Sasha Volkov in an audio recording.
"Many have no water at all for drinking. All the shops and pharmacies were looted four to five days ago.
"Some people still have food but I'm not sure for how long it will last. Many people report having no food for children."
Aid agencies have said the port city in southern Ukraine is facing an "apocalyptic" situation, with no water, power or heat for more than a week as Russian forces bombard it.
Attempted evacuations of civilians have failed, with Ukraine and Russia accusing each other of ceasefire violations.
Volkov said a black market has emerged where Mariupol residents can get vegetables but not meat, while medical supplies were scarce.
His audio message also depicted scenes where civilians struggled to keep warm and safe from Russian shelling in claustrophobic shelters.
"People are getting sick already because of the cold. They have nowhere to go," he said.
Some ICRC workers had managed to collect food to last for a few more days from damaged or destroyed buildings.
"We have started to get sick, many of us, because of the humidity and cold... We tried to achieve hygiene standards as much as possible but not always actually possible," he added.
International outrage at Mariupol's deteriorating humanitarian situation grew on Wednesday after an air strike hit a children's hospital, killing at least three people including a young girl.
Ukrainian President Volodymyr Zelensky and the European Union have called the incident a "war crime".
But Russia has said the building was sheltering ultranationalist Ukrainian fighters, describing the attack as a "staged provocation" to stoke anti-Russian sentiment.
Taking the strategically located city would allow Russia to link up forces in the annexed Crimea peninsula with troops in the eastern Donbas region.