Federal regulators on Tuesday charged Texas financier R. Allen Stanford and three of his firms with a "massive" fraud that centered around high-interest-rate certificates of deposit, and raided some of the companies' offices.

In a complaint filed in federal court in Dallas, the Securities and Exchange Commission alleged Stanford orchestrated a fraudulent investment scheme centered on an $8 billion CD program that promised "improbable and unsubstantiated high interest rates."

Stanford's assets, along with those of the three companies, were frozen. Stanford's firms include Antigua-based Stanford International Bank, broker-dealer Stanford Group Co. and investment adviser Stanford Capital Management, which are both based in Houston.

 Stanford, 58, is one of the most prominent businessmen in the Caribbean, with investment advisers around the world helping him grow a personal fortune estimated at $2.2 billion by Forbes magazine. His Stanford International Bank Ltd. said deposits surged from $624 million in 1999 to $8.4 billion in December.

The bank is based in the twin-island Caribbean nation of Antigua and Barbuda, which has carved out a niche as a tax haven and offshore base for Internet gambling. Stanford has deep roots in Texas, where he graduated from Baylor University, and still speaks with a slight twang.

But he travels in different circles now — knighted in 2006 by the islands' government, Stanford is known there as "Sir Allen." And last year he shook up the staid world of professional cricket by bankrolling the purse in a $20 million winner-take-all match in Antigua between England and a West Indies select team.