CNN
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Armed attackers launched a deadly “terror attack” on Turkey’s state aerospace company in the capital Ankara on Wednesday, government officials said.

At least four people were killed and 14 injured – three of them in critical condition – in the “terrorist attack” on the headquarters of the Turkish Aerospace Industries (TUSAS) on the outskirts of Ankara, Interior Minister Ali Yerlikaya said. Two attackers – a man and a woman – were killed, he added.

“I condemn this heinous attack. Our fight will continue with determination and determination until the last terrorist is neutralized,” Yerlikaya said. “May God have mercy on our martyrs. I wish our injured a speedy recovery.”

A video on social media, verified and geolocated by CNN, showed the moment an explosion rocked the TUSAS headquarters. After the explosion, a person with a firearm is seen running in what appears to be a parking lot.

Turkey is a member of the North Atlantic Treaty Organization. Mark Rutte, NATO’s secretary general, said he had spoken to Erdogan about the “very worrying” attack. “NATO stands with Turkey,” he said.

Ankara Mayor Mansur Yavas said he was “saddened” by the attack on TUSAS, a major defense company. Turkish Justice Minister Yilmaz Tunc said an investigation had been launched into the attack.

After the attack, the aerospace company’s chief executive, Mehmet Demiroglu, left a high-profile defense fair early to return to Ankara, state news agency Anadolu reported.

TUSAS was incorporated into Turkey’s Ministry of Industry and Technology in 1973 to reduce the “foreign dependence” of the country’s defense industry, according to its website.

“This is one of the largest defense companies in the country. It produces armed drones and fighter jets,” Ragip Soylu, head of the Turkish bureau for the news channel Middle East Eye, told CNN.

The attack took place while Turkish President Recep Tayyip Erdogan was in the Russian city of Kazan to attend the annual BRICS summit.

Russian President Vladimir Putin expressed his condolences after the attack.

‘You know how we feel about this. We condemn these kinds of demonstrations, regardless of their motivation,” Putin said in his opening speech to Erdogan, just hours after the attack in Ankara.

The US State Department is “monitoring reports” of the attack, a spokesperson told CNN.

This story and headline have been updated with additional developments.