Demonstrating its earnestness about rooting out tax fraud, the Internal Revenue Service has given $104 million to a former banker who helped expose tax evasion at the Swiss bank UBS AG.

Bradley Birkenfeld served two and a half years in prison for for his involvement in systemic tax avoidance at the Swiss banking giant, but the IRS also turned him into a weapon in its fight against overseas tax dodgers. With Birkenfield's help, the agency was able to slap the bank with a $780 million fine and obtain the names of thousands of potential American tax evaders.

"The IRS today sent 104 million messages to whistleblowers around the world - that there is now a safe and secure way to report tax fraud and that the IRS is now paying awards," Birkenfeld's lawyers, Stephen M. Kohn and Dean A. Zerbe, said in a statement. "The IRS also sent 104 million messages to banks around the world - stop enabling tax cheats or you will get caught."

The IRS called the intelligence Birkenfield provided "exceptional in both its breadth and depth," noting a trove of information relating to secret Swiss accounts that had escaped the notice of investigators.