WASHINGTON The scandal surrounding the collapse of U.S. energy giant Enron took a dramatic turn late Sunday when a U.S. Senate panel suddenly canceled its hearing on the matter because the company's former boss had refused to show up.

Kenneth Lay, the former chairman and chief executive officer who resigned from the company last month, said his lawyer that, "He cannot be expected to participate in a proceeding in which conclusions have been reached before Mr. Lay has been given an opportunity to be heard," attorney Earl Silbert said in a letter sent to Capitol Hill.

The refusal followed comments made by two U.S. lawmakers earlier in the day, in which they alleged corruption and other criminal wrongdoing behind Enron's much publicized filing for bankruptcy on December 2.

Appearing on NBC's "Meet the Press" television show, Democratic Senator Byron Dorgan, a member of the Commerce Committee, accused the energy conglomerate of misleading its investors and employees.

"This is almost a culture of corporate corruption," he complained.

Republican representative Billy Tauzin, who chairs the House Energy and Commerce committee which is also probing the Enron collapse, was even harsher, AFP reported.

"I think we're finding what may clearly end up being security fraud," he said on the same program.

Attorney Silbert argued that his client could not testify in such an atmosphere.

"These inflammatory statements show that judgments have been reached and the tenor of the hearing will be prosecutorial," he wrote.

The decision to cancel the Senate hearing was announced jointly by Democratic Senator Ernest Hollings, chairman of the commerce committee and Dorgan.

Lay has not been formally subpoenaed by congressional investigators and, therefore, doesn't run the risk of being held in contempt of congress for his refusal to testify, according to legal experts.

But the move is certain to further inflame passions on Capitol Hill where many lawmakers have already been seeing red over Enron's financial dealings and its treatment of its employees.

The animus toward the Houston, Texas-based corporation reached a boiling point late Saturday when a special investigative committee set up by the Enron Board of Directors released a scathing report detailing how top company executives used business partnerships to conceal mounting debt and make Enron's balance sheets look attractive to investors.

The scheme has allowed the executives to inflate the company's reported earnings by nearly one billion dollars from late 2000 to late 2001 and pocket millions in the process.

The investigative commission has in effect rejected statements by Lay's wife, Linda, who insisted in a television interview last week that all questionable transactions had been done behind the back of her husband.

Lay personally approved the arrangements under which his subordinates were permitted to engage in dealings with the partnerships, according to the report.