At least 12 people were killed in an explosion at a factory in Turkey’s Karesi district of Balikesir province on Tuesday.

The blast occurred on Tuesday morning at a section of the plant that collapsed under the force of the explosion, according to local officials cited by AFP.

Turkish officials said the cause of the blast is not yet known, as photos and videos circulating on social media appeared to show fire engulfing the facility.

Turkey is a key member of NATO and in recent years has become one of the most prolific defense exporters inside the bloc, with its combat drones featuring prominently on the Ukraine frontlines at the start of the war with Russia.

This is a breaking news story and will be updated shortly.