Andrew Fastow, the former chief financial officer of the disgraced energy giant Enron, has pleaded not guilty to defrauding investors as he appeared in court in Houston.

A federal grand jury has already indicted him on 78 federal charges of money laundering, fraud, conspiracy and obstruction of justice.

Prosecutors are hoping Andrew Fastow will dish the dirt on Kenneth Lay

If found guilty, Mr Fastow could be sentenced to several hundreds of years in prison and million-dollar fines.

The 40-year-old accountant is accused of creating and managing the complex web of partnerships that disguised the true state of affairs at the disgraced energy firm.

The indictments allege Fastow crafted multiple schemes that produced phantom profits and let him skim millions for himself, his family and inner circle.

More investigations

Enron collapsed at the end of last year with billions of dollars in debt, putting thousands of employees out of work.

Mr Fastow, who is the most senior former Enron manager yet to be targeted by the US authorities, is alleged to have made a personal fortune in kickbacks from the partnerships.

Meanwhile, another federal judge has announced a fresh investigation into whether Enron operated improperly when it acquired several small windfarms on the West Coast.

Judge Peter Young of the Federal Energy Regulatory Committee has called for hearings on 14 November to determine whether Enron acted improperly when it transferred ownership of several windfarms to its secret affiliates at inflated prices.

In search of truth

Mr Fastow has consistently insisted that he did not believe he committed any crimes.

"These charges are full of sound and fury, but the truth about Enron has yet to be told," his lawyer, John Keker, said.

"When the truth is told to a jury of 12 honest Americans, Andy Fastow will be set free."

But the federal authorities have not been convinced.

"The investigation into Mr Fastow's illegal activities continues," said Deputy Attorney General Larry Thompson.

"We will use every appropriate measure to recover the ill-gotten gains of these corporate schemers. Justice demands it."

No one in prison...yet

Prosecutors has been under pressure to bring a successful prosecution against Enron executives for some time.

But neither former chief executive Jeffrey Skilling nor Enron chairman Kenneth Lay, Mr Fastow's immediate superiors, has yet been charged.

President George W Bush has called for corporate fraudsters to go to jail.

But so far the only conviction has been of former Anderson accountant David Duncan, who approved Mr Fastow's transactions and later pleaded guilty in a court of law.

Mr Duncan has yet to be sentenced for his crimes.