Public health officials in California are investigating one of the country's biggest food distributors following a KNTV-TV report showing employees storing perishable food products in unrefrigerated metal sheds.

The station reported filming employees at Sysco Corporation using a dozen outdoor sheds around Northern California as both storage units and pick-up locations for delivering turkey, bacon, produce and other items to local restaurants, hotels and schools using their personal vehicles. On its website, the Texas-based company claimed to service about 400,000 customers and operate out of 180 facilities in the U.S., Canada and Ireland.

"Our company policy states that Sysco-controlled drop-sites must be secure and equipped with refrigerator/freezer units," Sysco said in a statement to KNTV. "Sysco San Francisco has immediately ceased its practices in relation to these drop-sites and will review and implement the correct practices with its sales and delivery teams."

KNTV reported that according to employees, the practice had been taking place for years. The California Department of Public Health began its investigation after being alerted by the station.

Watch KNTV's report, aired Tuesday night, below.

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