NEW YORK — The ousted CEO of commodities brokerage Refco Inc. was charged with securities fraud yesterday for hiding up to $545 million in bad debts from federal regulators and investors, a federal prosecutor said.

Phillip R. Bennett, 57, of Gladstone, N.J., was arrested Tuesday night and charged in a criminal complaint unsealed in U.S. District Court in Manhattan, said U.S. Attorney Michael Garcia.

A day earlier, the brokerage announced that $430 million in debts to the company, funneled through a firm controlled by the ousted chairman and chief executive officer, was concealed through a number of secret transfers. Much of the debt may have been uncollectible, but the transfers made it hard to detect.

In court, Assistant U.S. Attorney David Esseks fought bail, calling Bennett a flight risk, a British citizen with a half billion dollars in assets who told a colleague in a tape conversation Monday that he was going to Europe within two days.

U.S. Magistrate Douglas F. Eaton granted bail, saying Bennett could go free after pledging a Manhattan apartment and his New Jersey home as collateral and agreeing to electronic monitoring. It amounted to a $50 million bond with $5 million in cash.

Esseks said prosecutors had developed an "extraordinary case" that involved a "staggering" loss of money for investors that could result in a life sentence if Bennett is convicted.

But defense attorney Gary P. Naftalis said "there's no case here." He said his client had already pledged his shares in Refco to secure a bank loan that repaid the $430 million loan with interest on Monday.

"He received no personal profits from this," Naftalis said.

The lawyer said prosecutors rushed their case. According to Naftalis, Esseks acknowledged he did not know that Bennett had pledged all of his Refco stock to secure the loan.

Garcia said prosecutors and U.S. postal inspectors worked around the clock since Monday to develop evidence that Bennett "had played an active role" in hiding the debt from the public and securities regulators.

Garcia noted that the public invested hundreds of millions of dollars last summer when Refco, the largest U.S. retail commodities broker dealer, issued stock in an initial public offering.

On Monday, Refco said that its earnings statements dating back to 2002 "should no longer be relied upon" and that it will delay filing its next quarterly report. Bennett was put on leave and Chief Operating Officer William Sexton, who was due to retire, was tapped as CEO.