The Federal Trade Commission said Thursday it has temporarily shut down a Belize real estate investment scheme that it says targeted U.S. senior citizens, calling it the largest such scam it has ever encountered.

James Kohm, associate director of the FTC’s division of enforcement, said Sanctuary Belize raked in $100 million while marketing false promises about dream retirement homes in a luxurious resort. He said the scheme primarily targeted U.S. residents and small-business owners near retirement age.