Drone explosion hits Russia's Black Sea Fleet HQ, cancelling Navy Day holiday

Russia has held a Naval parade in St Petersburg, despite cancelling observances of the Navy Day holiday in Sevastopol following a drone explosion hitting Russia's Black Sea Fleet headquarters.

Russian President Vladimir Putin inspected the parade and, in an address in St Petersburg, said Russia will "provide protection firmly and by all means".

"The key thing here is the capability of the navy forces," he said.

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"It can respond with lightning speed to all who infringes on our sovereignty and freedom, it fulfills successfully and honorably strategic tasks on the borders of our country and in any area of ​​the World Ocean."

The Russian president also mentioned the "latest Zircon hypersonic missile systems", which he said "have no countertypes in the world and no barriers".

"Dear comrades, their delivery to the Russian armed forces will begin in the coming months," he added.

The drone-borne explosive device detonated at the headquarters of Russia's Black Sea Fleet, injuring six people, officials said.

The explosion in the city of Sevastopol, on the Crimean peninsula that Russia annexed from Ukraine in 2014, caused the cancellation of observances of Russia's Navy Day holiday.

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The Black Sea Fleet’s press service said the drone appeared to be homemade.

It described the explosive device as "low-power" but Sevastopol mayor Mikhail Razvozhaev said six people were injured in the blast.

There was no immediate information on where the drone began its flight. Sevastopol is about 100 miles south of the Ukrainian mainland and Russian forces control much of the mainland area along the Black Sea.