One of the main drivers of Turkey’s defence industry became the target of a deadly attack on Wednesday afternoon. The assault on state-run Turkish Aerospace Industries (TUSAS) has killed at least five and injured 22.

It was not clear 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.

A series of explosions and gunshots were heard at TUSAS, an engine manufacturer for the Turkish defense industry.