UPDATE 1-US warns Tyson on seafood violations at Texas site

* FDA: “Serious violations” of food safety rules

* Texas plant makes seafood soup

* Company says food safe, documentation is issue

WASHINGTON, Dec 1 (Reuters) - U.S. regulators have warned Tyson Foods Inc TSN.N about "serious violations" of food safety regulations at a Texas plant where the company makes seafood soup, a letter released on Tuesday said.

Seafood soups and sauces made at a Fort Worth, Texas, plant were “prepared, packed or held under insanitary conditions whereby they may have been rendered injurious to health,” the Food and Drug Administration said in a Nov. 13 letter to the company.

Tyson Foods spokesman Gary Mickelson said the company believed “this is really a documentation issue involving the plant’s written food safety plan.” He said the FDA wanted Tyson to document a temperature control procedure for thawing some seafood, and the company had made that change.

“Contrary to the impression left by the FDA letter, our Fort Worth plant is clean and sanitary and the products produced there are safe to eat,” Mickelson said via email.

The shrimp and crabmeat that FDA inspectors observed being thawed at the plant was discarded, he added.

The FDA sends dozens of warning letters each year. Most issue raised are resolved without further action, although the letters can lead to product seizures or other actions.

Shares of Tyson Foods were up 1.3 percent to $12.17 in afternoon trading on the New York Stock Exchange, matching a broad-based gain for stocks.

The FDA posted the letterhere. (Reporting by Lisa Richwine; Editing by Tim Dobbyn) ((Reuters Messaging:; +1 202 310-5691))