A cafe and hotel near the town of Chorlyj on the Black Sea coast have been hit, according to reports.
"According to preliminary reports, more than 50 people were injured and 24 people were killed," wrote Russian-installed governor Vladimir Saldo on Telegram.
Russia's Federal Investigative Committee announced that an investigation has been launched, saying that over 20 people have been killed.
According to Russian Foreign Ministry spokeswoman Maria Zakharova, this is a terrorist attack against civilians.
Ukrainian authorities have not commented on the details of the attack.
