South Korea’s tax agency said Friday that it had begun inspections of mask filter manufacturing companies to prevent illegal profiteering amid the new coronavirus outbreak.

The National Tax Service has examined 12 local manufacturers that produce nearly 95 percent of the nation’s supply of filter material -- melt blown nonwoven fabric.

Melt blown or MB filters are the core material for hygiene masks. Depending on the percentage of particle blockage, they are classified into three types and assigned different “KF” numbers -- 80, 94 and 99.

With face masks running out fast amid the COVID-19 outbreak, the NTS has become concerned over panic buying or illegal trafficking of mask filters, which may cause manufacturing delays.

Prior to the inspections of mask filter makers, the NTS detected some cases of illegal profiteering while inspecting face mask manufacturing and distribution firms.

The tax agency will look for unrecorded cash transactions, smuggling, hoarding filter materials, and high-priced trafficking.

In cases of illegal profiteering, the tax agency will immediately subject the firms to tax audits.

By Jie Ye-eun (yeeun@heraldcorp.com)