Tesla has sued a former worker for allegedly stealing about 26,000 confidential files in his first week of work at the company, in accordance to a court filing.

The organization stated on Friday that within three days of being hired, software program engineer Alex Khatilov “brazenly stole thousands of trade secret that took Tesla years to develop” and transferred them to his private Dropbox, a cloud storage service.

Tesla stated that when confronted by Tesla’s security team, Khatilov claimed he had only transferred a couple of personal administrative documents. Khatilov informed the New York Post the files ended up in his Dropbox by mistake when he was trying to make a backup replica of a folder on his computer.

Tesla stated the files, which represented “200 man-years of work”, have been extraordinarily treasured by the company and when exposed to its competitors would give them a roadmap to copy Tesla’s innovation.

It said Khatilov’s was a member of an elite group of Tesla’s 40 employees out of 50,000 that had access to the intellectual property. No other employee was involved in the IP theft.

Tesla’s security group detected the file downloads on January 6, after Khatilov was employed on December 28, and confronted him by means of videocall as he was working from home, in accordance to the court filing.

Tesla said throughout this call, Khatilov delayed sharing his screen with the team, during which time “he hurriedly starts deleting records from his computer. However, investigators were still capable to view hundreds of private documents uploaded to his Dropbox, which Khatilov claimed he somehow forgot.

Khatilov, who informed the New York Post that he was unaware he was being sued till the newspaper called him on Friday, was fired the same day.