Barclays Bank PLC sued hedge fund manager Ritchie Capital Management and its principal, Thane Ritchie, accusing them of concealing more than $150 million in investments made in the collapsed Petters Group Worldwide and affiliates.

Now bankrupt, the Minnetonka-based Petters Group was raided in September by the FBI acting on information that the company may have cheated at least 20 investors. Principal Tom Petters, accused of leading a $3 billion fraud, is being held without bail.

"Thane Ritchie made the decision to invest significant sums" from two of his firm's hedge funds with Petters at a time when those funds "were supposed to be winding down," Barclays said in a complaint filed Monday in Illinois state court in Chicago. The bank is a unit of London-based Barclays Plc. Shares in that commercial banking and investment house have declined almost 74 percent this year.

Ritchie Capital Management, based in Lisle, Ill., and 19 related entities and funds are named as defendants in the Barclays suit, as are Ritchie and four other company executives. The bank says it's owed at least $380 million.

The firm's outside spokesman, Justin Meise of River Communications, said in an e-mailed statement that the Barclays suit "lacks merit."

Ritchie-related entities could be owed almost $225 million, according to a list of unsecured creditors filed in the Petters case in U.S. Bankruptcy Court in Minneapolis. While one of those entities, Ritchie Capital Structure Arbitrage Trading Ltd., is said to be owed as much as $12.5 million, that debt is listed as contingent and disputed.

While that company is a defendant in the Barclays suit, hedge funds Ritchie Structured Investments Ltd. and Ritchie Targeted Investments Ltd. aren't named in the Petters debt schedule.

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