An Arkansas federal judge on Friday ordered Tyson Foods Inc. (TSN) to pay $500,000 , the maximum criminal fine allowable, and serve a year's probation for willfully violating worker safety regulations that led to a worker's death.

The violations took place at a Tyson plant in Texarkana, Ark., that recycled poultry products into protein and fats for the animal food industry.

Prosecutors said the recycling process produced toxic gas at the plant and Tyson was aware of the safety threat. They said Tyson didn't take sufficient steps to implement controls or provide protective equipment to employees to protect against the risk of exposure.

As a result, a Tyson employee repairing equipment in the plant was overcome by the toxic gas and later died, prosecutors said.

"The Justice Department takes its enforcement responsibility seriously and companies that ignore these laws and risk their employees' lives will be prosecuted," said John Cruden, the acting head of the department's Environment and Natural Resources Division.

A Tyson spokesman couldn't immediately be reached for comment.

-By Brent Kendall, Dow Jones Newswires; 202-862-9222; brent.kendall@dowjones.com