Dallas, Feb 10 - Peanut Corp of America, at the center of a nationwide salmonella scare, has shut its Texas plant after tests showed possible contamination in some of its products, health officials said on Tuesday.
One of the company's plants in Georgia has been identified as the source of food poisoning that has sickened at least 600 people in 44 states and Canada, more than half of them children, and may be linked to eight deaths.
The salmonella outbreak has forced one of the biggest recalls in U.S. history, involving more than 1,800 products ranging from snacks and ice cream to dog treats.
The Texas Department of State Health Services said Peanut Corp voluntarily closed its Plainview facility on Monday evening "after laboratory tests of sample products from the plant indicated the possible presence of salmonella in some."
"It does not appear that any of the implicated products -- peanut meal, granulated peanuts and dry roasted peanuts -- have reached consumers," it said in a statement.
FBI officials in Atlanta and Virginia said on Monday they had joined the U.S. Food and Drug Administration in a criminal probe of the company.
"There were simultaneous searches of the different locations," said Dee Rybiski, a spokeswoman for the FBI field office in Richmond, Virginia, who confirmed that FBI agents searched the peanut company's headquarters in Lynchburg, Virginia.
"It's an FDA case. The FBI is just providing the resources," she said.
The outbreak is the latest in a series involving tainted lettuce, peppers and spinach that have eroded public confidence in food safety and renewed calls for change at the FDA by the Government Accountability Office, consumer groups, the food industry, Congress and the Obama administration.
The House Government Reform and Oversight Committee had a hearing scheduled for Wednesday on the issue.
A Peanut Corp spokeswoman was not available for comment. The company has said it is cooperating with the FDA's investigation.