Thick fog has enabled Russian troops to move further into the key strategic city of Pokrovsk in eastern Ukraine.
Ukraine's 7th Airborne Assault Corps says weather conditions, particularly dense fog, have prompted Moscow to intensify its bid to get increasing numbers into the ruined city and then encircle Ukrainian forces.
Russian forces have spent more than a year trying to capture the city, and Ukrainian President Voloydymyr Zelensky says the fog has favoured Russian attacks and the situation remains difficult.
A video that has gone viral on social media shows Russian soldiers openly driving through a hazy road on civilian cars and motorbikes.
The BBC has verified the location where the video was filmed as the southern outskirts of the town on the Selidove-Pokrovsk highway.
