Russia's defense ministry has officially denied information circulating on social media that Ukrainian forces have started counteroffensive moves.
The ministry made the unusual announcement on Thursday. It said the statements on social media about "defense breakthroughs" on the front lines are not true.
Earlier in the day, Russian bloggers reported possible Ukrainian advances around the eastern city of Bakhmut and the southern region of Kherson.
Russian daily Kommersant said the possible start of Ukraine's counteroffensive had been reported.
Observers say the ministry's official denial indicates the Russian government is nervous about the timing of the counteroffensive.