Mongolian authorities grounded a suspected Turkish air force jet Friday after witnesses said assailants snatched a Turkish man associated with a religious group Ankara has branded as terrorists.
In recent weeks, Turkey's intelligence agency has conducted operations abroad against associates of US-based preacher Fethullah Gulen -- who Ankara says was behind a 2016 failed coup.
As many as five men grabbed Veysel Akcay from outside his home in Mongolia's capital Ulaanbaatar Friday morning and threw him into a minibus, according to friends and eyewitnesses.
The 50-year-old is director of a school in Mongolia that is alleged to be associated with Gulen, although teachers there denied the connection in response to questions by AFP.
When he failed to show up for work, concerned family and friends notified the police.
Meanwhile, Akcay's abductors had taken him to Genghis Khan international airport, where a small passenger jet landed around 1.00 pm (0500 GMT).
The plane -- with call sign TT4010 -- is operated by the Turkish Airforce, according to data on flight tracking site flightradar24.com.
It was the beginning of a more than eight-hour standoff between the captors and Mongolian authorities, who refused to allow the plane to leave the runway.
As authorities summoned Turkish officials from their embassy in Mongolia, parliamentarians and protestors clutching signs demanding Akcay's release gathered at the airport.
As the standoff dragged on, Mongolian Vice Minister of Foreign Affairs Battsetseg Batmunkh warned Turkish embassy officials that any attempt to abduct a person from Mongolia's territory would constitute "a serious violation of Mongolia's independence and sovereignty".
Turkey's Minister of Foreign Affairs Mevlut Cavusoglu denied the accusations during a telephone call to his Mongolian counterpart Tsogtbaatar Damdin, according to the Mongolian Ministry of Foreign Affairs.
But officials were not convinced: "We are an independent nation. Do you think anyone can do abductions in our country?" parliamentarian Baasankhuu Oktaybri wrote on Twitter.
The plane took off at 9:25 pm. Akcay was not on it, a Mongolian transportation official said on Twitter.
Turkey accuses Gulen of ordering the July 2016 failed overthrow of President Recep Tayyip Erdogan. He strongly denies the claims.
Gulen's movement built up significant influence in Turkey and overseas, particularly in Central Asia, Africa and the Balkans, especially via its education network.
Ankara has outlawed the movement as a terror organisation but followers insist they promote peace and moderate Islam.
Turkey has carried out a series of overseas operations against suspected members of the movement in places such as Kosovo, Gabon and more recently Ukraine.
Last week a Turkish blogger accused of links to Gulen was deported from Ukraine as part of an operation by MIT while another individual was detained in Azerbaijan recently and sent back to Turkey.
In Turkey over 77,000 people were arrested over alleged links to the movement during a two-year state of emergency imposed after the coup bid in a crackdown criticised by Ankara's Western allies.