The Wall Street Journal reportedthat a former UBS AG banker who helped the U.S. government unleash an international crackdown on tax evasion was awarded $104 million in what is believed to be the largest-ever whistleblower payout to an individual.

The Journal said that Bradley Birkenfeld began cooperating with U.S. authorities in 2007, while still at UBS. He provided prosecutors with detailed descriptions of the bank’s efforts to promote tax evasion and confessed to running errands for rich clients, including one instance when he sneaked diamonds into the U.S. in a toothpaste tube.

The Journal noted that Birkenfeld, who was also implicated, pleaded guilty in 2008 to one count of conspiracy to defraud the U.S., a felony, and was given a 40-month sentence.

To read the Wall Street Journal article, click here.