Ukraine has been stepping up long-range strikes as the war grinds on, with Russia's westerly second city now hit. The latest attack on Saint Petersburg takes place as an event long known as "Russia's Davos" kicks off.
Ukrainian drones on Wednesday struck energy and military targets in Saint Petersburg as Russia hosts a major economic forum.
Officials said a number of infrastructure sites were damaged, though no deaths were reported.
What do we know about the drone... [1834 chars]