Law enforcement officers block a street following a reported combat drone attack on the Russian Black Sea Fleet's headquarters in Sevastopol, Crimea July 31, 2022. REUTERS/Stringer

According to Russian reports, the headquarters of the Black Sea Fleet in the city of Sevastopol on the Crimean peninsula, which is claimed by Ukraine, was attacked with a drone. Five people were injured on Sunday, said the governor of Sevastopol, Mikhail Rasvozhayev, in his blog on the Telegram news channel.

The drone had hit a courtyard in the headquarters. Russia annexed Crimea in 2014.

“Early this morning, Ukrainian nationalists decided to spoil our Navy Day,” Razvozhayev wrote. Celebrations of the day observed in many regions of Russia have been canceled for Sevastopol.

Russian authorities in regions bordering Ukraine repeatedly complain of attacks from the neighboring country.

According to preliminary information, the object of the attack was a drone, Rasvoschajew said. The injured are staff members of the Russian Black Sea Fleet. There are no dead.

“I ask that you remain calm and stay at home if possible,” Rasvozhayev wrote. The domestic secret service FSB is working on the clarification of the case.

Russian President Vladimir Putin inspects a parade of warships, airplanes and thousands of soldiers on Sunday in Saint Petersburg for “Navy Day”. The Kremlin chief also used the traditional event as a demonstration of power a good five months after the start of the Russian war of aggression in Ukraine.

Parades honoring the naval forces and their various fleets are planned in several regions of Russia.