The Secret Service is investigating the theft of Mitt Romney's tax records, the AP reports

A letter sent anonymously to Tennessee political and newspaper offices demanded $1 million to prevent their disclosure.

Romney’s accounting firm, PricewaterhouseCoopers, said there is no evidence any Romney tax files were stolen. The letter said the returns were stolen in late August during a Watergate-style break-in at the company’s accounting offices in Franklin, Tenn.

The Nashville City Paper has more on the hackers who claim to have pulled off the heist. They would like to be paid in Bitcoins, a virtual currency that exists in a legal gray area.