Assailants set off an explosive and opened fire in an attack Wednesday on the Turkish state-run aerospace and defense company TUSAS, killing three people and wounding several, officials said.
At least two of the attackers died, Interior Minister Ali Yerlikaya said. He said 14 people were wounded.
Selim Cirpanoglum, mayor of Kahramankazan district, said the attack on the company on the outskirts of the capital, Ankara, had abated but could not provide more details.
It was unclear who may be behind the attack. Kurdish militants, the Islamic State group and leftist extremists have carried out attacks in the country in the past.
Private NTV television said assailants arrived at an entrance to the complex in a taxi during a changing of the security personnel. At least one of the assailants detonated a bomb as other attackers managed to enter the complex.
Helicopters were seen flying above the complex, the station reported.
TUSAS designs, manufactures and assembles civilian and military aircraft, unmanned aerial vehicles and other defense industry and space systems.
Security camera images from the attack, aired on television, showed a man in plainclothes carrying a backpack and holding an assault rifle.
At least one woman, also carrying an assault rifle, was among the assailants, according to the camera footage.
Earlier, media reports said an explosion followed by gunfire was heard at the complex and employees were taken to a safe area.