The Russian military said it was training after the St. Petersburg airport was briefly closed

MOSCOW (Reuters) – Russia’s Defense Ministry said it had conducted an air defense exercise using interceptor planes after St Petersburg’s Pulkovo airport was forced to suspend all flights on Tuesday for an hour.

The government of Russia’s second city announced the lockdown on its official Telegram channel without providing a reason for comment, as unconfirmed media reports said an unidentified object, such as a drone, had been spotted in the area.

City officials said later on Tuesday that flights had resumed and that a temporary airspace ban within 200 km (124 miles) of Pulkovo had been lifted by 1200 local time (0900 GMT).

In a statement issued about an hour after the resumption of flights, the Russian Ministry of Defense said that it was conducting exercises that included sending combat aircraft into the western airspace of Russia.

“During the training, the air defense forces worked on detecting, intercepting and identifying targets, as well as interacting with emergency services and law enforcement agencies,” Russian news agencies quoted the ministry as saying.

It added that the fighter plans carried out sorties as part of the exercises. The exercises were not previously announced and caused several flights to be rerouted and flight plans rescheduled for the rest of the day.

Data from the FlightRadar24 website showed several St Petersburg-bound flights returning to their destinations early Tuesday, while the airspace closure also affected flights en route to Russia’s Kaliningrad region, which requires planes to fly over St Petersburg.

By 1200 local time, flights towards St. Petersburg resumed, and planes resumed landing and taking off at the airport.

At a media briefing after flights resumed, Kremlin spokesman Dmitry Peskov declined to comment on the reasons for the hour-long disruption, but said President Vladimir Putin was fully aware of the situation.

Reporting by Reuters. Written by Jake Cordell. Editing by Andrew Osborne

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