It’s chilling news.

Three samples of ice cream produced in China tested positive for coronavirus Thursday, regulators in the country’s Tianjin municipality said.

All employees at the Tianjin Daqiaodao Food Company, about 90 miles southeast of Beijing, were immediately quarantined and tested for the virus, Chinese media outlet Global Times reported. Of the 1,600 employees, 700 tested negative and 900 results were not immediately released.

The ice cream was made with ingredients imported from New Zealand and Ukraine, regulators said. It remains unclear how the virus was detected during routine food inspections.

Authorities said the COVID-19-contaminated dessert was part of a batch of 4,800 boxes, of which about 2,700 had been purchased by markets and wholesalers in Tianjin.

Chinese food inspectors and contact tracers were still working Friday to track all the potentially contaminated boxes.

A virologist told Sky News in the U.K. that the COVID-19-positive ice cream was “probably a one-off” and said there was no need to panic.