AMNA NAWAZ: A drone was shot down today in Lithuania by a NATO jet.

It's unknown from where the drone was launched, but it's the latest in a series of drone incursions and sabotage attacks across the northern nations of NATO.

Lithuania borders Russian-allied Belarus and the Russian enclave Kaliningrad.

And as Moscow relentlessly presses its destructive campaign in Ukraine, it's also now overtly and covertly confronting NATO.

Here's Stephanie Sy.

STEPHANIE SY: Overnight, for the first time in Lithuanian airspace, fighter jets shoot down a potentially armed drone, as seen in this video.

The alliance tracked the drone for roughly 30 minutes not far from residential areas before the Italian air force destroyed it over this field.

Lithuania says there is still much to investigate.

LAURYNAS KASCIUNAS, Lithuanian National Security and Defense Committee (through translator): It is not yet clear whether this was a drone that had been diverted and lost its way, as has often happened in our recent history, or whether it was a deliberate provocation.

No version has been ruled out yet.

STEPHANIE SY: But authorities added the drone likely carried explosives and entered from Russian ally Belarus.

Lithuania neighbors a critical choke point directly between Belarus and Russia's Kaliningrad region, positioning it on NATO's front line with Moscow.

The drone was intercepted near the village of Pratkunai 60 miles west of the capital, Vilnius.

Lithuania's defense minister did not confirm whether the drone was Russian, but said: ROBERTAS KAUNAS, Lithuanian Defense Minister (through translator): If we do not force Russia to negotiate for peace, then unfortunately such incidents in the Baltic region may become more frequent.

STEPHANIE SY: Drone incursions have become an increasingly familiar sight and source of concern across NATO's eastern flank.

NATO fighter jets have previously intercepted drones over the other two Baltic states, Estonia and Latvia.

Some of those were suspected to be Ukrainian drones that strayed off course.

But in recent weeks, officials from several NATO countries accused Russia of sabotage, surveillance, and plans to attack a German airport with a drone carrying explosives.

There were also other signs of tension across the region this week.

In Denmark, officials say a Russian warship fired flares near a Danish military helicopter in the Baltic Sea, a move the country's prime minister said was meant to intimidate and divide.

The Russian ambassador to Denmark said the Danish helicopter was at fault, adding it was not the first time Danish aircraft carried out -- quote - - "dangerous maneuvers" near Russian warships.

The E.U.

's top diplomat, Kaja Kallas, said the recent incidents were not accidents, but calculated.

KAJA KALLAS, Foreign Affairs High Representative, European Commission: We have seen Russia's dangerous, reckless full display past 48 hours.

And one thing is very clear.

Putin will not stop unless he's stopped.

So as Russia is willing to take greater risks, Europe must impose a greater cost.

STEPHANIE SY: As Russia refuses to back down, NATO's Baltic allies are policing the skies on edge.

For an inside look now at this growing confrontation with Russia across NATO territory, we turn again to Ambassador Doug Lute.

He served as the U.S.

envoy to NATO from 2013 to 2017 and spent years as a senior Army commander in postings across Europe before that.

Ambassador, welcome back to the "News Hour."

The most recent drone incursion into Lithuania follows a drone hitting a Ukrainian passenger train less than a mile from the border with two days ago.

Is this an escalation or is this more of the same types of violations we have seen from Russia in recent years?

LT.

GEN.

DOUGLAS LUTE (RET.

), Former U.S.

Ambassador to NATO: Well, I think these two drone incidents that you mentioned are part of a larger pattern and a pattern that's been going on, playing out over several years, with attacks that involve drones, as you have mentioned, along the eastern flank of NATO.

But it goes beyond that.

It goes to cyberattacks.

It goes to misinformation and disinformation campaigns, election interference, cutting of undersea cables in the Baltic Sea, and so forth.

And all of these together are part of a campaign by Russia to both test NATO and to distract NATO, and, in particular, distract NATO from its support to Ukraine.

STEPHANIE SY: What are the real-world risks of these incursions, Ambassador, not just for the safety of the people in these states that border Ukraine and Russia, but for the possibility of open war with NATO?

How much is that a fear, in your mind?

LT.

GEN.

DOUGLAS LUTE: Well, of course, conflict with NATO is largely defined by Article 5 of the NATO Treaty, which essentially says an attack on one ally shall be considered by the others as an attack on them.

So all of these -- all of these activities, which move right up to the boundary, right up to the border of the definition of armed attack, are really playing with fire, because there's always the chance of misperception or the chance of an accident or an unintended consequence.

Imagine, for example, if the drone that hit the passenger train just across NATO's boundary with Ukraine, just across the Polish-Ukrainian border, just this weekend had intended to be only a signal, but had been slightly misguided and hit a load of passengers to include senior former European and U.S.

officials.

That's the kind of misperception or miscalculation that can lead to rapid and unbounded escalation.

STEPHANIE SY: E.U.

officials say these incidents were deliberate acts.

Why does Putin seem to have, as NATO put it last month, an increasing tolerance for risk?

And does the U.S.'

more hands-off stance have anything to do with that?

LT.

GEN.

DOUGLAS LUTE: I think Putin sees an opportunity here to accomplish by way of these hybrid attacks or these less -- lower than Article 5 attacks, a chance to divide the alliance.

And this has, of course, been a political objective of Russia and before Russia of the Soviet Union.

And that is essentially to break the link, the transatlantic link between the United States and our European allies.

And Putin sees an opportunity here because he sees the perception among European allies that the White House has moved away from what has been a standing leadership and commitment of the alliance that stood for nearly seven decades.

But now you see some questions, some doubt imposed by this administration and causing our European allies to question U.S.

commitment.

So Putin sees an opportunity and he's taking advantage of it.

STEPHANIE SY: Well, is NATO prepared for this kind of low-intensity hybrid war?

It seems that some states take it very seriously, Poland, the Baltics, Germany.

But are others less concerned, and has Putin successfully divided the alliance?

LT.

GEN.

DOUGLAS LUTE: He hasn't been successful yet.

But your observation that those closest to the border to the east are most concerned.

So, it turns out, even here in the -- well into the 21st century, geography still counts.

So the Baltic states, Poland, Bulgaria, Romania, Turkey, and so forth, those bounding -- Finland -- those bounding the eastern flank of the alliance are paying the most attention.

Putin has not been successful yet, but he is being persistent, and he is very, very patient in this approach to divide the alliance.

STEPHANIE SY: That is Ambassador Doug Lute.

Thank you, sir, as always, for bringing your perspective.