For at least a year, GPS signals have been jammed across the region, with experts blaming Russia.

However, the fact that the plane, a Boeing 737 cargo jet operated by DHL, crashed just short of the runway at Vilnius Airport indicates that something unexpected occurred in the flight's final seconds.

TalTech Center for Digital Forensics and Cyber Security senior lecturer Dr. Adrian Venables said that while "the signal can be very easily jammed, and so GPS signal can be lost using very simple technology, which is widely available," this is "illegal to use in most countries, but it is not a difficult thing to do – to jam GPS."

Nevertheless, this would not have been the cause of Monday morning's crash, he added.

"The issue in this situation is that the aircraft would not have been relying on GPS for navigation at the time of the accident," Venables explained.

While initial speculation pointed to GPS interference as the cause, by the time the plane was approaching the runway, it was already using radio communications.

In any case, flight crews can switch to alternative systems to avoid accidents in the event of GPS interference, which has been observed affecting air traffic over Estonia.

Ivar Värk, board chair of Estonian air traffic control (Lennuliiklusteenindus), told "Aktuaalne kaamera": "We have experienced GPS disruptions; it is hard to say what caused them, but they have happened. However, our pilots continue to fly safely, as we have alternative systems in place."

At this early stage in the accident investigation, the most likely causes are technical failure or human error-related aerodynamic issues. Lithuania's crisis management center is focusing on the first of these possibilities.

The plane, which had flown from Leipzig, Germany, crashed at around 5:30 a.m. on Monday, an incident captured on security footage from several locations.

One person has been confirmed dead, and three others were injured, all from the flight crew.

Estonian air traffic controller Üllar Salumäe said that the plane's attitude was such that it should have reached the runway even if neither of its two engines were functioning. "It was in the final approach phase, close to landing," he said.

Given heightened security concerns over Russian hybrid warfare GPS jamming, some speculated the accident was caused by such an attack. However, Lithuania's outgoing Prime Minister Ingrida Šimonyte urged people on social media "not to jump to premature conclusions."

Lithuania's defense minister, Laurynas Kasčiunas, added: "There are no signs or evidence that would definitively confirm this was an act of sabotage."

Another theory was an explosion from hazardous cargo, but DHL said no such items were on board. Fires had this year broken out at Leipzig Airport's logistics center on two separate occasions and arising from cargo carried on the same DHL route, prompting suspicions of hybrid warfare activities.

DHL Lietuva CEO Mindaugas Pivoriunas stated that the 31-year-old Boeing 737-476(SF) aircraft belonged to their partner, Spanish carrier Swiftair, and that DHL had no information on the cargo.

The crash did not cause major disruptions to Vilnius airport operations, though some departures were delayed.

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