Multiple explosions rocked the Crimean city of Simferopol around 9 p.m. local time on Saturday, according to video on social media and local news.
Explosions were also reported in Sevastopol, the headquarters of Russia’s Black Sea Fleet; in a Russian military barracks in Sovietske; and in the settlements of Hvardiiske, Dzhankoi and Nyzhniohirskyi.
The blasts come after Moscow stepped up its missile attacks on Ukraine last week, and around the same time Ukraine launched attacks on occupied Melitopol and Donetsk, controlled by Russian-backed separatists.
The exact circumstances surrounding the explosions are unclear:
Sergey Aksenov, the Russian-appointed Crimean chief, said the region had activated its air defenses but did not specifically outline details of a potential attack.
“The air defense system worked over Simferopol,” he wrote on Telegram. “All services are operating as usual.”
The unofficial Crimean media portal Krymskyi Veter said the explosion at a Russian military barracks in Sovietske set the building on fire, killing some people and injuring others.
A pro-Russian Crimean channel claimed the fire at the barracks was caused by “reckless handling of fire”.
“Two people died. Now all the soldiers, about two hundred people, are housed in another room,” he said.
And Mikhail Razvozhaev, governor of Sevastopol, said the explosions in his area were due to firing exercises.
Ukrainian officials have not commented on the reported explosions in Crimea. CNN is unable to verify what caused the explosions, nor the extent of the damage and casualties.