SIOUX FALLS, S.D. (AP) — Virginia-based Smithfield Foods announced Sunday that it is closing its pork processing plant in Sioux Falls until further notice after hundreds of employees tested positive for the coronavirus — a step the head of the company warned could hurt the nation's meat supply.

The announcement came a day after South Dakota Gov. Kristi Noem and Sioux Falls Mayor Paul TenHaken wrote to Smithfield and urged the company to suspend operations for 14 days so that its workers could self-isolate and the plant could be disinfected.

The plant, which employs about 3,700 people in the st...