A video circulating on social media shows a huge fire that engulfed a large Rosneft-owned oil refinery in the southern Russian town of Tuapse on the Black Sea coast in the early hours of Thursday morning. The refinery's vacuum unit caught fire, said Sergei Boiko, the head of Tuapse district, adding in a post on his Telegram channel that there were no casualties. He warned local residents not to post videos from the scene "to avoid adverse consequences." Boiko didn't identify the cause of the fire, but numerous Telegram channels said it was the result of a drone strike. Russian...