A military drone
Illustrative image of a military drone. The type of craft downed by the Turkish Army has not been confirmed iStock

The Turkish air force has shot down an "unidentifiable" aircraft on the Syrian border in what appears to be a worrying escalation of the proxy war in the war-torn country. The aircraft reportedly intruded into Turkish airspace and was downed in line with the rules of engagement after being warned three times, the Turkish army reported.

"Today, an aerial vehicle of unknown nationality has been detected inside our airspace on the Syrian border, and when it continued its movement despite being warn three times, our aircrafts on patrol mission on the border fired and shot down the vehicle within the rules of engagement," a statement on the Turkish army website read. "Turkish Armed Forces is executing its tasks with determination within the rules of engagement."

Turkey's NTV said the aircraft was an unmanned drone. That was confirmed by an official to Reuters.

Local Haberturk TV shared on Twitter an alleged picture of the drone:

The Russian defence ministry said all its planes in Syria safely returned to their base and all drones are operating as planned, according to RIA Novosti news agency.

Earlier in October, Turkey scrambled a pair of F-16s to intercept Russian warplanes which had allegedly violated its airspace. Russian president Vladimir Putin has launched air strikes in Syria which the Kremlin said could last between three to four months against opponents of their ally, embattled president Bashar al-Assad.

Turkey's president Recep Tayyip Erdogan has warned that the bombing campaign is a grave mistake and questioned Russia's long-standing support to Assad regime.