A drone attack on Sunday that targeted the Russian fleet located in the port of Sevastopol, Crimea, wounded five, the city's mayor, Mikhail Rrazvozhayev said. The attack coincides with Navy Day.

Razvozhayev said all festivities have been canceled following the wounding of five people including employees and military staff.

"An unidentified object flew into the courtyard of the Fleet Headquarters, according to preliminary data, it is a drone. Five people were injured, they are members of the fleet headquarters, and there were no deaths," Razvozhayev said on Telegram.  

"This morning, Ukrainian nationalists decided to spoil the Day of the Russian Fleet," he added. The celebrations have been canceled for security concerns, and the residents have been asked to remain indoors "if possible".

A Naval parade, however, is due to take place in Saint Petersburg later in the day, and it will be attended by President Vladimir Putin.

Razvozhayev later revealed that the Military Procuratorate concluded that the attack was carried out by an improvised explosive-laden drone.

"The drone that attacked the [Black Sea] fleet headquarters was launched by Ukrainian saboteurs from the vicinity of Sevastopol," a local security source told Al Mayadeen.

The Russian Navy "performs its tasks in protecting the country's security to the fulles and shows the whole world its high readiness and outstanding preparation," Russian Defense Minister Sergey Shoigu said in a speech on the occasion of Navy Day.

Russian Security Council Deputy Chairman Dmitry Medvedev warned on Thursday that any attempted attack on Crimea would be considered a declaration of war against Russia, and subsequently could ignite a third world war if the attempt is conducted by a NATO member.

Earlier this week

Air forces from seven various NATO countries joined its aircraft and ground systems for a training event in Romanian airspace earlier this week, a press release from the alliance said on Saturday. The training sought to conduct coordinated combined air-to-ground drills "demonstrating interoperability and preparedness".

"This enhanced Vigilance Activity enables forces to address a large spectrum of threats, from tactical to strategic, emanating from many directions," claimed Lieutenant Colonel Raphael, part of the planning team for the activity at Allied Air Command.

According to Raphael, the participating air assets are modeling how to weaken an adversary's integrated air defense system to allow follow-on operations and the freedom of maneuver necessary for defensive operations in NATO and international airspace.

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