A hacker allegedly stole Mitt Romney’s tax returns and is demanding $1 million in Bitcoins for silence. The hacker also sent a USB drive and letter to the Republican and Democratic party offices in Williamson County, Tenn. as proof, VentureBeat reports.

Williamson County Republican party executive director Jean Barwick confirmed that the U.S. Secret Service has taken the USB drive and letter from the GOP party office to examine it and see if this is a hoax or a real situation.

“We don’t know what this will turn into, if anything,” Barwick told VB. “[The Secret Service] didn’t say what they would do with it.”

In a letter, the hacker says the records were stolen from PricewaterhouseCoopers in Franklin, Tenn.

PricewaterhouseCoopers PR managing director Chris Atkins commented, “We are aware of the allegations that have been made regarding improper access to our systems. We are working closely with the United States Secret Service, and at this time there is no evidence that our systems have been compromised or that there was any unauthorized access to the data in question.”