A privacy row his broken out in the US after a 20-year-old computer salesman found a GPS tracking device on his car.

Two days after Yasir Afifi removed the device he was confronted by six FBI agents and police officers – who asked for the gadget back.

Afifi cooperated with the officials, maintaining that he had not done anything to provoke the FBI's attention.

Wired.com reports that upon taking his car to a garage Afifi discovered the GPS tracker, which was attached to the car's chassis with a magnet.

Later on, Afifi's friend Khaled posted photos of the device on reddit, where it was identified as an Orion Guardian ST820 manufactured by a company that deals exclusively with law enforcement.

Although Afifi has never been affiliated with any type of questionable organisation and is a US-born citizen, he says he is on a federal watch list and is often taken aside at airports.

The incident comes after the Ninth US Circuit Court of Appeals' recently reaffirmed the government's right to secure GPS devices to vehicles without a warrant.

FBI Special Agent Joseph Schadler told ABC news: "Court decisions have consistently upheld that there is no warrant necessary for GPS tracking of a vehicle when the vehicle is in a public space."