A Northern California Costco store on early Saturday morning recalled nearly 40,000 pounds of cooked chicken linked to a salmonella outbreak that has sickened more than 300 people nationwide.

The Agricultural Department announced the store’s recall of 9,000 rotisserie Foster Farms chickens and related Kirkland Farms products such as soup, chicken salad and leg quarters purchased at Costco’s South San Francisco store between Sept. 11 and Sept. 23.

Costco officials couldn’t be reached Saturday. A recorded message warns customers to discard or return any leftovers of the Foster Farms chicken products.

Most of the chicken implicated in an outbreak that is still ongoing has been purchased raw by consumers. The Costco chicken implicated in the outbreak is cooked on the store’s premise and sold as “ready to eat.”

Sampling by the USDA in September linked raw chicken processed by three Foster Farms processing plants in Central California to the outbreak. The Centers for Disease Control and Prevention said the plants in Fresno and Livingston are the “likely source” of the “Heidelberg” salmonella strain rarely found in the United States.

The outbreak started in March and continues to sicken people. The CDC said 42 percent of victims were hospitalized, about double the normal rate.

The particular strain of salmonella in the outbreak is resistant to many antibiotics, making it more dangerous.

The CDC reported Friday that 317 people in 20 states and Puerto Rico have been stricken by the tainted chicken. About 230 of the victims live in California, the CDC reported.

The Agriculture Department is threatening to shut down three California poultry processing facilities linked to a salmonella outbreak that has sickened 278 people across the country.

USDA said Wednesday that Foster Farms, owner of the three facilities, has until tomorrow to tell the department how it will fix the problem. The company was notified Monday.

No deaths have been reported.

Salmonella can contaminate meat during slaughter and processing and is especially common in raw chicken. The infections can be avoided by proper handling and cooking of raw poultry.

The pathogen causes diarrhea, abdominal cramps and fever within a few days of eating a contaminated product and can be life-threatening to those with weakened immune systems.