ST. PAUL — A cluster of dozens of coronavirus cases detected at a Sioux Falls meatpacking plant didn't appear to have an immediate impact across the border in Minnesota, Gov. Tim Walz said Thursday, April 9, but state officials are on heightened alert following news of the outbreak.

South Dakota health officials on Wednesday reported that 80 workers at Smithfield Foods in Sioux Falls had tested positive for COVID-19, the illness stemming from the coronavirus, and the plant on planned to temporarily close for deep cleaning over the weekend.

The processing plant brought in hogs to be processed from Iowa, Minnesota and South Dakota and some of the workers there also lived and worked second jobs in Minnesota. The Minnesota connections and proximity to the border raised concerns, but didn't appear to spur increased case counts in southwestern Minnesota, Walz said.

"We haven’t seen it yet but I’m very worried," Walz told reporters.

The state would continue to track potential cases in that area, Walz said, and the administration planned to continue discussions with food producers and processors in Minnesota to ensure they could continue operating and that workers remained safe. Smithfield is among several production plants to close due to the COVID-19 pandemic.

Walz said the state would aim to take steps to test workers in food production facilities for antibodies indicating they'd already had the illness once Mayo Clinic Laboratories made the tests available more broadly. And he would recommend checking employees for symptoms before they enter the plants.

Without adequate safety measures, additional plants could shutter, leaving holes in the food supply chain, Walz said. But for now, he said, the chain remains intact.

“At this point in time, we’re not hearing of any disruption to the supply chain, but that is our deep concern," he said. ”If we send everybody back without doing this, and we shut down Hormel or we shut down General Mills, that becomes a national problem, that becomes not just a Minnesota problem.”