Shortly after midnight Saturday in Ukraine, the country's newly-installed top commander, General Oleksandr Syrsky, announced that he had ordered troops to evacuate the city. Surrounded in three directions by the Russian army, Ukrainian soldiers in the city found themselves in a rapidly-tightening noose. 

"Based on the operational situation around Avdiivka, in order to avoid encirclement and preserve the lives and health of servicemen, I decided to withdraw our units from the city and move to defense on more favorable lines," said Syrsky in a Facebook post. 

While its authenticity can't be confirmed, video circulating on social media purportedly shows Ukrainian armored vehicles executing a fiery but mostly orderly retreat: