The Pentagon said the US shot down a Turkish drone on Thursday after coming close to American troops in northeastern Syria.

US military officials repeatedly warned Ankara about flying drones near US troops.

For all the latest headlines, follow our Google News channel online or via the app.

Turkey claimed that the drone was not theirs, according to Reuters, which was taken out by an American F-16 fighter jet. Defense Secretary Lloyd Austin spoke to his Turkish counterpart later about Ankara’s military activity near US forces in Syria, Pentagon Press Secretary Brig. Gen. Pat Ryder told reporters.

The top US military general, Gen. CQ Brown, also spoke to his Turkish counterpart about the need to follow common deconfliction protocols to ensure the safety of US troops in Syria.

Ryder said that Turkish drone strikes were being carried out inside a declared US-restricted operating zone, and a drone was less than half a kilometer away from American troops before the F-16 took it out.

The US commander responsible for operations in the area took the decision to shoot down the drone, and US troops were relocated to bunkers, Ryder said.

But he noted that there was no initial indication that Turkey was intentionally targeting US forces, calling it a “regrettable incident.” No US forces were harmed.

The US and Turkey have been at odds over Syria as Washington continues to back and support the Syrian Democratic Forces (SDF). The SDF has been a critical ally in the fight against ISIS and other terrorist groups.

Turkey has also previously threatened a ground attack inside Syria against US-backed fighters, which the US has repeatedly warned against.

Read more: Top US military general warns Turkey against Syria incursion