Federal agents have achieved another milestone as they boast of arresting a person who is believed to be a spy working for Microsoft.

This is the twelfth this year in when a step is taken to bust the spy ring happening in the premises of US.

The alleged spy, Alexey Karetnikov was working at company's headquarters of Microsoft in Redmond.

He belonged to the Microsoft Software Design Engineer in Test (SDET) team who was responsible for testing code run in Microsoft products such as Windows.

Federal agents claimed that Karetnikov was just in the "early stages" of his spying, without extracting much of the important information.

However recent reports claim that of the twelve spies arrested, most had day jobs at tech companies, and some had families as well.

The first ten were deported to Russia in a prisoner swap, while the eleventh spy remains in hiding.