Powerful explosions were heard in early hours on Saturday the Ukrainian city of Mykolaiv, mayor Oleksandr Senkevich said in a social media post.
"There are powerful explosions in the city! Stay in shelters!" Senkevich wrote on the Telegram messaging app.
It was not immediately known what caused the explosions. Reuters could not independently verity the report.
Air raid sirens sounded across the whole Mykolaiv region before the blasts.
