At least four people were killed and 14 others wounded in an attack on Wednesday afternoon at the headquarters of Turkish aerospace and defence company, TUSAS, near Ankara.
Local broadcasters showed footage of several armed assailants entering the building amid reports of gunfire and a loud explosion.
Images showed them carrying assault rifles and backpacks.
The exact circumstances of the events are not yet clear, but the authorities have described the incident as a “terrorist attack”.
Turkey’s president Recep Tayyip Erdogan said that two attackers – a man and a woman – had been killed.
No-one has yet claimed responsibility for the incident.
In the past, Kurdish militants, the Islamic State group, and leftist extremists have carried out attacks in Turkey.
TUSAS is one of Turkey most important defence and aviation companies with over 10,000 employees.
It designs, manufactures, and assembles both civilian and military aircraft, including Kaan, the country’s first national combat aircraft.
Local media are reporting that prosecutors have launched an investigation into the incident.
