Fresh-cut roma tomatoes grown in Mexico and distributed to Costco by Boskovich Farms Inc. may have been contaminated with salmonella and are part of a voluntary recall Expo Fresh LLC initiated in September.

Boskovich was not named in the Sept. 12 recall notice on the Food and Drug Administration’s website. However, the Oxnard, Calif., company and its diced roma tomatoes were included in the agency’s Oct. 7 weekly enforcement report.

No illnesses have been reported in connection to the tomatoes, according to the FDA. The recall was initiated after a routine sampling by government officials returned positive results for salmonella.

None of the diced tomatoes remain in the stream of commerce and the company is cooperating with the FDA as the agency investigates the situation, said Dave Murphy, director of food safety for Boskovich. He declined to name the supplier of the romas, citing business confidentiality, but said Costco was Boskovich’s only customer to receive any of the suspect lots.

Boskovich supplied Costco with 5-pound clear plastic overwrapped black poly trays and 24-ounce clear plastic bags of diced roma tomatoes.

Murphy said the recalled Boskovich fresh-cut romas are part of the tomatoes voluntarily recalled by Expo Fresh LLC in September.

Expo Fresh LLC imported the recalled tomatoes from Mexican growers, said Bob Schachtel, sales manager of the San Diego-based company. Schachtel said Boskovich Farms is not a customer of Expo Fresh, so one of Expo’s customers apparently sold the tomatoes to the Oxnard company.

Taylor Farms, Salinas, Calif., also distributed the Expo Fresh romas. The Taylor Farms products went to Costco, Safeway, Vons, and Pavilion stores in California, Nevada and Arizona, according to the initial recall notice. Some of the recalled romas distributed by Taylor Farms were whole and some were part of salad kits.