Finland’s national airline Finnair has temporarily suspended flights to Estonia’s second largest city after two planes were prevented from landing due to alleged GPS jamming by Russia.
The flights, which were en route to Tartu, were forced to turn back to Helsinki last Thursday due to the disruption.
The cause of the GPS jamming was not immediately known but suspicion has centred on Russia.
Approaches to the airport currently rely on GPS signals, however, other tools can be used and Finnair has suspended flights from April 29 to May 31 while alternative technology is installed.
“Most airports use alternative approach methods but some, such as Tartu, use only methods that require a GPS signal to support them,” said Jari Paajanen, Finnair’s director of operations.
Finnair said GPS interference has been increasing over the past two years.
“Finnair pilots have reported interference especially near Kaliningrad, the Black Sea, the Caspian Sea and the Eastern Mediterranean,” the company said.
Mr Paajanen said when the GPS is not being relied upon for airport approach, disruption to the service does not typically result in safety issues.
“Our pilots are well aware of the issue and the aircraft have other navigation systems that can be used when the GPS system is unserviceable,” he added.
However, Estonian Foreign Minister Margus Tsahkna said jamming carried out by Russia is so dangerous that sooner or later it will cause a crash, the Baltic News Service reported.
“So this is a deliberate action that interferes with our lives lived in a dangerous situation and this can be considered as a hybrid attack,” Mr Tsahkna told Estonian broadcaster ERR.
GPS jamming and spoofing have become increasingly prevalent in Eastern Europe, the Black Sea and the Middle East, all areas close to conflict zones, industry group OpsGroup said.
Use of GPS is a growing in aviation, replacing radio beams used to guide planes into land.
Estonia will raise the issue of GPS interference with its neighbours and intends to discuss it with the EU and Nato, said Mr Tsahkna.
"It is a fact that Russia affects GPS devices in our region’s airspace," the minister said via a representative.
He did not provide evidence for the claim.
Estonian authorities are working with Finnair to find solutions to restore air traffic in Tartu, Mr Tsahkna added.
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Neither the Kremlin nor Russia's Defence Ministry immediately replied to requests for comment.
British intelligence believes Russia jammed the GPS signal on an RAF aircraft carrying Defence Secretary Grant Shapps from Poland last month as the plane flew close to its Baltic exclave of Kaliningrad.
Sources said mobile phones could not connect to the internet for about 30 minutes and the plane had to use other methods to determine its location.
RAF planes taking off from Cyprus are reportedly regularly affected by Russian equipment but it is said to be rare for the signal on a flight carrying a high-profile figure to be jammed.
Earlier this month, Germany said Russia was probably behind a series of disturbances affecting navigation in the Baltic region.
The German Defence Ministry pointed to Kaliningrad as their source, though it declined to give any details citing "reasons of military security."
Moscow did not comment on the accusations at the time.
Meanwhile, Russia is planning to target Moldova with a wave of so-called “hybrid” attacks in the run-up to its presidential election and referendum on joining the EU later this year, according to people familiar with UK intelligence assessments.
Britain will share intelligence with Moldovan authorities to help them counter the perceived threat from Russian operatives in the coming months, said the sources, who asked not to be named.
Moldova’s Foreign Minister, Mihai Popsoi, will meet UK Europe Minister Nusrat Ghani in London on Tuesday to discuss “subversive Russian meddling”, while defence ministers of the two countries will also meet, the British Foreign Office said in a statement.
Nato chief Jens Stoltenberg, meanwhile, said it was "not too late" for Ukraine to win the war, despite its outmanned and outgunned military struggling in the face of Russian advances while waiting for stalled arms deliveries from allies.
Ukrainian forces have been on the defensive for months, while Russia's troops have inched steadily forward on the front line.
On Monday. Russia claimed to have captured a second village in as many days in eastern Ukraine, while a missile strike on the Black Sea port of Odesa killed at least four people and wounded 27.
Moscow has for weeks been pressing its advantage at the front, an effort it has accelerated in recent days before crucial US weapons reach Kyiv's exhausted frontline forces.
