A missile has hit the headquarters of Russia's Black Sea navy in Crimea, a local Moscow-the Russian-installed governor of Sevastopol says.
In a post on Telegram, Mikhail Razvozhayev says a fragment fell near the Lunacharsky Theatre in the largest city in Russian-occupied Crimea.
He says emergency services are on the scene and information about victims is being clarified.
Videos on social media show smoke billowing from the building.
BBC Verify has confirmed the footage to be genuine and new.
The reports of a new strike on Russia's Black Sea fleet follow recent attacks by Ukraine on infrastructure and military targets in occupied Crimea.
A number of targets have been hit on the peninsula's western coast, including an attack on the military base in the port city of Sevastopol - which destroyed a submarine and a warship.
Meanwhile Ukrainian President Volodymyr Zelensky is in Canada on an unannounced visit - his first there since Russia's invasion of Ukraine began.
On Thursday, the US approved $325m (£265m) in further funding for Kyiv - but not the long-range missiles Zelensky wants.
Diplomatic tensions are on the rise elsewhere after Zelensky criticised Poland, Slovakia and Hungary for banning imports of Ukrainian grain.
Poland says it will no longer send weapons and ammunition to Ukraine, although it will continue with previously agreed deliveries.