The missile which struck Poland on Tuesday evening, killing to people, may have been one from the S-300 surface-to-air series, Minister of Defense Hanno Pevkur (Reform) says.
The S-300 family of missiles were first developed by the Soviet Union and are in present-day use by the forces of both Russia and Ukraine.
Pevkur told ERR Wednesday morning that: "There has been speculation on whether it could have been an S-300. However, the investigation is needed to reveal whether this is in fact the case or not."
The minister said that, having spoken to his Polish counterpart, Mariusz Blaszczak, on Tuesday night, it is clear the investigation into the incident is still ongoing.
"No one wants to give any final confirmation on what type of missile it was and where it had come from. It is known that it was of Russian origin, but what exactly it is still needs to be ascertained," he said.
The possibility of the missile having been fired by Ukrainian forces in response to incoming Russian missiles amid heavy fighting in western Ukraine cannot be ruled out, Pevkur added.
"At the moment it appears from opinions from various experts that it could have been an anti-aircraft missile, one which can also be used to attack ground targets," he said.
This means that the missile would not have been fired from Russian territory, given its trajectory and range.
"It is also the case that this type of missile cannot travel far outside Russian territory, because its range is simply not sufficient. However, at this point in time this is pure speculation, and we will have to wait for Poland's official confirmation, after which we will be able to make better informed and longer-range conclusions," Pevkur continued.
"Ukraine will do everything to protect its country, and naturally if Russia attacks on such a large scale, using missiles, then of course Ukraine will also do its part to neutralize these missiles."
Russia had been conducting such a large-scale airstrike against Ukraine Tuesday, involving 90 Russian missiles and also 10 Iranian drones, the minister noted.
Minister: Ukraine took down bulk of 90 missiles Russia fired at it Tuesday
Ukrainian air defenses brought down over 70 of the Russian missiles, along with all 10 of the drones, he said.
Experts are to gather at the Ministry of Defense in Tallinn this morning, Wednesday, , Pevkur said, to review the picture as it now stands and to make decisions based on that.
The prime minister will also be consulted on whether the matter should be discussed at cabinet level also, Pevkur added.
Interior minister: Government not taking a position until facts established
Meanwhile Interior Minister Lauri Läänemets (SDE) told ETV morning show "Terevision" that the government will not take a position on whether the missile was fired by Russian or Ukrainian forces, but instead will wait for the facts to be established, adding that if it was the result of Ukrainian action, this was understandable in the context of the constant Russian attacks its forces are under.
Pevkur also refused to be drawn on whether the missile could have been fired from Belarusian territory. The country's regime is a staunch ally of the Russian Federation, and Belarus also borders with Poland.
Russia is also trying to provoke a humanitarian catastrophe in Ukraine, including in the West of the country, as winter arrives and amid soaring energy prices.
Pevkur: We have a clear picture of airspace situation on Poland-Ukraine border and surrounding region
Pevkur said that the Polish authorities will be able to determine the facts from the fragments left after the missile's impact, which can also be collated with NATO data which tracked the missile's path.
This could also be seen in the light of POTUS Joe Biden's comments Tuesday evening that given that trajectory, the missile could not have been fired from Russian territory.
Poland and its NATO allies have a very clear picture of the region's airspace, Pevkur added.
As to next steps, the minister reiterated that Poland's decision, for instance on whether to invoke Article 4, is awaited, a decision which in turn hinges on the Polish investigation into the incident.
Estonia and the EU as a whole was paying very close attention to developments, along with Poland and NATO, he added, while more clarity is expected through the course of the day.
This will also entail close cooperation and consultation with NATO member states.
While the decision on whether to trigger Article 4 is one for the Polish government, Pevkur said doing so would be "reasonable", noting this had already happened in the case of the annexation of Crimea in 2014, and the beginning of the Russian invasion of Ukraine in February this year.
NATO member Turkey has also triggered Article 4 several times, he added.
If it transpired that the missile had indeed been fired by Russian forces, this would result in the more drastic triggering of Article 5, Pevkur added.
Article 5 defines a casus foederis and commits each NATO member state to consider an armed attack against one or more member state to constitute an armed attack against all member states, a situation which can be followed by military action on the part of the alliance.
It is still too early to talk about such an outcome, however, Pevkur continued.
"There is certainly no need to sow panic. As the Polish president also said, for now we must stay calm, draw the right conclusions and then the next decisions can be made," he went on.
Government will meet Wednesday afternoon
The government's security cabinet is to convene Wednesday afternoon to discuss the situation.
Prime Minister Kaja Kallas (Reform) said Wednesday morning that: "The incident that took place in Poland yesterday is extremely serious. We are actively communicating with Poland and other allies to find out the exact circumstances of the incident."
"Poland is a strong ally of ours within NATO, and they can be sure that Estonia is committed to the principles of collective defense," Kallas, who has already spoken with Hanno Pevkur and with Minister of Foreign Affairs Urmas Reinsalu, added, per a government office press release.
"My condolences to the relatives of those who were killed," she went on.
Editor's note: This article was updated to include comments about the incident from the prime minister.
Editor: Andrew Whyte, Urmet Kook, Mait Ots