Getty ImagesSmoke rises as rescuers arrive at the scene
An explosion has been reported outside the headquarters of an aviation company near Ankara, in an incident the authorities have labelled a terror attack.
The country's Interior Minister Ali Yerlikaya posted on X: "Unfortunately, we have martyrs and injured people."
Initial images shown by the NTV television channel were of a large cloud of smoke in front of the entrance of Turkish Aerospace Industries (TAI), which is located some 40km (25 miles) outside the capital.
According to local media, gunshots were heard.
They said that the blast took place around the time of a shift change, and staff had to be directed to shelters.
Firefighters and medical teams have been dispatched to the scene.
It is not clear how many people are involved in the attack.
Some outlets have carried a photograph purporting to show one suspect climbing over a turnstile and entering the building holding a gun.
Ankara metropolitan mayor Mansur Yavas said in a statement he was “deeply saddened” by the news.
“I wish God's mercy upon our martyrs and a speedy recovery to our wounded. We condemn terrorism. My condolences."
Turkey’s Justice Minister, Yilmaz Tunc, announced on X that the Ankara Chief Public Prosecutor’s Office has launched a “judicial investigation” into the incident.
TAI is a key player in Turkey’s aerospace industry, designing, developing and manufacturing various aircraft for commercial and military use.
The blast took place as a major trade fair for defence and aerospace industries was going on in Istanbul this week.
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