Spanish fighter jets taking part in a NATO Air policing mission over Estonia have been temporarily suspended from completing their duties, after one of the pilots erroneously fired an armed missile during a training flight.
The missile has a self-destruct mode, but it's not known if it was activated.
The military said the Eurofighter Typhoon from the Spanish Air Force - part of NATO's Baltic air-policing mission - accidently launched an AMRAAM-type, air-to-air missile in a practice area in southern Estonia on Tuesday afternoon (local time).
The Estonian Air Force launched a search operation on Tuesday evening.
Authorities said the last presumed location of the missile was 40 kilometres (25 miles) north of the Estonian town of Tartu, some 60 kilometres (37.2 miles) from the Russian border.
The NATO multi-role military plane, a Eurofighter Typhoon, fired the missile by accident during a training exercise over the village of Pangodi, south-west of Tartu.
After the incident the jets returned to an air base in Siauliai in northern Lithuania where they are based.More news: Chris Pratt's 'Cowboy Ninja Viking' Movie Delayed Indefinitely
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The Estonian Prime Minister Juri Ratas called the incident "horrible" and "regrettable".
He added: "I am sure that the Estonian defence forces will. make every effort to make sure that nothing like this happens again".
According to UK's The Telegraph, Spain's Defence Ministry was investigating the cause of the misfire.
Ratas and Stoltenberg also discussed the results of July's Brussels Summit and agreed that increasing the alliance's defense expenditures is important.
"However, after saying this, I will add that many civilian and military organizations play their role in ensuring global air security".
Six Spanish Eurofighters and approximately 130 personnel deployed to Siauliai in May, as part of NATO's Baltic Air Policing mission, which is now led by Portugal. The Spanish Eurofighter detachment comprised of six jets.