These are the first criminal charges against Mr Ebbers

The complaint accuses the telecoms company - which is now known as MCI - and the former executives of breaking state laws by giving false information to investors.

The action is the first time Mr Ebbers has faced criminal charges.

WorldCom filed for the US' largest bankruptcy in July 2002 following an accounting scandal which is now thought to have reached $11bn.

Allegations

WorldCom's former chief financial officer Scott Sullivan, who was also named in the Oklahoma complaint, has already faced federal charges.

The other four former executives named were former controller David Myers, former director of general accounting Buford Yates, former director of management reporting Betty Vinson and former director of legal-entity accounting Troy Normand. These four have pleaded guilty to previous federal charges.

We're looking forward to working with the Oklahoma attorney general's office as we work to put the past behind us Claire Hassett, MCI spokeswoman

"We allege the company and these six employees executed a scheme to artificially inflate bond and stock prices by intentionally filing false information with the Securities and Exchange Commission," said state attorney general Drew Edmondson.

"Securities analysts and the investing public, including the state of Oklahoma, used this information when making investment decisions."

Mr Edmondson added that the company and employees had been charged because they all stood to profit from the scheme.

"This is not some rogue employee trying to line his own pockets," he said.

"This was a conscious decision made for the benefit of the company."

Reid Weingarten, a lawyer for Mr Ebbers, said the Oklahoma charges contained no specific evidence of wrongdoing by the former chief executive, and added that he expected Mr Ebbers to be cleared.

'Not new news'

The charges come just a fortnight before MCI is due to start court proceedings to try and emerge from bankruptcy.

On Tuesday the firm agreed to abide by a 78-point plan set out by court-appointed monitor Richard Breeden which was aimed at improving internal controls over how the company is run.

"We're looking forward to working with the Oklahoma attorney general's office as we work to put the past behind us," said MCI spokeswoman Claire Hassett.

"The fact the former WorldCom executives committed fraud is not new news. They've been out of the company for months."

MCI has already reached a $750m settlement with the US Securities and Exchange Commission.

However, the firm is also under criminal investigation and Oklahoma's Mr Edmondson said he believed other states would file lawsuits.