The airspace over a St Petersburg airport was temporarily closed on Tuesday morning amid unconfirmed reports that an unidentified object such as a drone had been spotted flying over it.
The government of Russia’s second city said on its official Telegram channel that it had halted all flights at Pulkovo Airport until 12pm local time (9am GMT).
Data from the Flight Radar website showed a number of domestic flights headed for St Petersburg turning back to their destinations.
The closure also appeared to be affecting flights on route to the Russian exclave of Kaliningrad, which requires planes to fly over St Petersburg.
The state-run TASS news agency said that airspace within a 200km(124-mile) radius of Pulkovo had been closed until 1320 local time, citing an unnamed source.
Officials did not provide a reason for the suspension.
An unconfirmed media report from online Russian news outlet Baza said an unidentified object had been spotted in the sky and that fighter jets had been dispatched to investigate.
The RIA Novosti news agency had earlier reported, citing a source in the city’s emergency services, that an unidentified object had been spotted, prompting the initial closure.
They later said that the jets had not found anything.
By 12pm local time, flights had resumed flying towards St Petersburg, the FlightRadar24 website showed.
The suspension came amid heightened security concerns in the Kremlin as Vladimir Putin’s illegal war in Ukraine continues.
On Monday anti-Russia activists in Belarus said they used drones to down of one the Russian president’s spy planes.
The AWACS Beriev A-50U aircraft, worth a reported £274m, was “significantly damaged”, according to the Belarusian Hajun project.
The group said central parts of the aircraft, its avionics and radar antennae were hit.
On Monday low-cost airline Wizz Air confirmed it would suspend all flights to and from Moldova due to safety concerns.
The announcement came after a Russian missile was fired over Moldovan airspace earlier in February.
In a statement, the Hungarian budget airline said: “Safety of the passengers and crew remain Wizz Air’s number one priority.
“Following the recent developments in Moldova and the elevated, but not imminent, risk in the country’s airspace, Wizz Air has made the difficult but responsible decision to suspend all flights to [the capital] Chișinău from 14 March.”
