According to the Russian information, it was about three drones, which did not cause any damage. Neither that nor who is behind it has been confirmed, but the incident late on Monday is interpreted as yet another step in Ukraine's ongoing bombing campaign against Russia's infrastructure for fossil fuels. Tiumen has been attacked by Ukraine before, in August, but the targets this time are described by Ukrainian military bloggers as record-long away. Approximately 210 miles from the Ukrainian border corresponds to more than the distance between Stockholm and Rome.
Earlier, during the night to Monday, a gigantic fire was reported on the occupied Crimea, after Ukrainian drones attacked Feodosiya, the area's largest oil terminal.
The Financial Times has reported that since August, 16 of Russia's total 38 oil refineries have been hit in Ukrainian attacks. Media in Kyiv describe it as a way to knock out the trade in fossil fuels, which is Russia's economic engine.
The broader drone warfare is also increasing from both sides. Ukraine accuses Russia of terrorist warfare, when drones virtually every night strike against civilian targets.
And both the night to Monday and the night to Tuesday, Ukraine struck back with major attacks. The first night, Russian authorities counted over 250 drones shot down, and during the second night, the number was over 180. Even wreckage from shot-down drones can be very dangerous, and the night to Monday, several Russians are said to have been killed in the attacks.