A Spanish fighter jet pilot accidentally fired an air-to-air missile during drills close to the Russian border.
Estonia's military said it was looking for the remains of the missile launched from a Eurofighter Typhoon on Tuesday afternoon during a mock dogfight in the south of the Baltic country, which is a Nato ally.
The multi-role fighter is part of the alliance’s air-policing mission in the region. It erroneously fired an AMRAAM (advanced medium range air-to-air missile)-type missile which was last seen 24 miles north of Estonia’s second city, Tartu.
The projectile has a built-in self-destruct system designed for such accidents, but Nato believes it may have landed on the ground.
Tartu is about 30 miles west of the Russian border.
Juri Ratas, Estonia's prime minister, called the incident “extremely regrettable" but confirmed there were no human casualties.
“I am sure that the Estonian defence forces will, in cooperation with our allies, identify all the circumstances of the case and make every effort to make sure that nothing like this happens again,” he added.
The Typhoon – also flown by the UK’s Royal Air Force – was taking part in drills alongside a second of its type and two French Mirage 2000 jets, the Agence France Presse news agency reported.
Spain has launched an investigation into the error, which its defence ministry said took place “without causing any harm”.
“The air-to-air missile has not hit any aircraft,” it added.