By David Ingram and Toni Clarke

WASHINGTON, Feb 21 (Reuters) - Four years after a salmonella outbreak linked to tainted peanut butter sickened hundreds in the United States and killed nine, authorities have charged the former owner of the company and several employees with fraud, conspiracy and obstruction of justice.

Federal prosecutors on Thursday alleged the group covered up the presence of salmonella in its peanut products for years, going so far as to create fake certificates showing the products were uncontaminated even when laboratory results showed the reverse.

The charges carry penalties of up to 20 years in jail, although none carry a mandatory minimum sentence, prosecutors said.

"When those responsible for producing or supplying our food lie and cut corners, as alleged in the indictment, they put all of us at risk," Stuart Delery, head of the U.S. Justice Department's Civil Division, said in a statement.

The peanut scandal led to one of the largest food recalls in U.S. history and forced Peanut Corporation of America (PCA), the manufacturer, into liquidation. Former owner Stewart Parnell, 58, is among those charged, as is his brother, Michael Parnell, 54, a food broker at P.P. Sales who worked on behalf of the peanut company.

Lawyers from Gentry Locke Rakes & Moore LLP, who represent Stewart Parnell, said in a statement they were disappointed that the government had decided to pursue an indictment and were planning a "vigorous defense."

"While Mr. Parnell and others associated with PCA have to date remained silent on the circumstances surrounding the government's salmonella investigation, as this matter progresses it will become clear that Mr. Parnell never intentionally shipped or caused to be shipped any tainted food products capable of harming PCA's customers," the law firm said.

Their statement also said U.S. health regulators were regularly in contact with PCA about its food handling policy and were well aware of its salmonella testing protocols, and made no objection to the testing policies or protocols in place.

At a press conference in Washington on Thursday, Delery said company officials had lied to inspectors from the U.S. Food and Drug Administration, which found that PCA produced peanuts under unsanitary conditions and failed to take adequate precautions to keep rodents and insects out of its plant in Blakely, Georgia.

Delery said the Justice Department would do everything possible "to protect Americans who have done nothing more than eat a peanut butter and jelly sandwich."

William Marler, an attorney who represented victims of the contamination, said the indictments will have a far reaching impact on the food industry.

"Corporate executives and directors of food safety will need to think hard about the safety of their product when it enters the stream of commerce," he said. "Felony counts like this one are rare, but misdemeanor charges that can include fines and jail time can and should happen."

Those affected by the outbreak welcomed news of the 76-count indictment.

"I'm ecstatic," said Jeff Almer, whose mother died after eating tainted peanut butter. "I would equate it to wishing for something to happen more than anything else you ever wanted in life, and waiting years for it to occur."

"This has been my life's mission for the last four years since my mom died - to try to get some justice," he said.

In addition to the Parnells, charges were also levied against Samuel Lightsey, 48, a former operations manager at the plant, and Mary Wilkerson, 39, who held various positions including receptionist, office manager and quality assurance manager.

Another employee, Daniel Kilgore, 44, has pleaded guilty to mail and wire fraud and to the introduction of adulterated food into interstate commerce. He waived an official indictment.

A conviction for fraud or obstruction of justice carries a maximum prison sentence of 20 years, while illegally introducing tainted food into interstate commerce carries a three-year maximum.

Actual sentences could be much lower, said Michael Moore, U.S. Attorney for the Middle District of Georgia, who said he expects those charged to appear in court within the next week.

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