A yearlong investigation has uncovered what tax authorities in the U.S. and Canada believe is a tax-shelter scheme that would allow affluent investors to claim massive losses by investing in phony offshore companies with money withdrawn from retirement accounts, according to The Wall Street Journal. The paper reports that investors were told they could put the money in the bogus companies and then bring the cash back, tax-free, a scheme that reportedly involved hundreds of individuals and tens of millions of dollars. The U.S. and Canada are part of newly created Joint International Tax Shelter Information Center, which also includes Australia and the U.K., and the latest scheme came to light through a tip from the Canadians.