Lady Gaga and Justin Timberlake may have been the targets of hackers trying to make money on their unreleased singles, said German authorities who are investigating the case.

The two men are believed to have hacked into the computers of singers including Lady Gaga, Justin Timberlake and Kelly Clarkson, in a bid to sell unreleased music files.

The files were obtained from a number of computers including some belonging to managers and people working closely with the stars.

“I can’t say whether the laptop sitting on Lady Gaga’s nightstand was among them, but I think that’s pretty unlikely,” Ralf Haferkamp of the Duisburg prosecutor’s office said in an interview with Deutsche Welle.

German police say that the pair used invasive programmes called Trojans to tap into the private computer networks, downloading music, credit card details, emails and photographs.

As well as selling some of the music they stole, the men obtained a naked picture of American singer Kesha, reportedly having sex. Authorities say the pair tried to blackmail the singer, but no money was handed over.