Ninety-six people are in police custody, awaiting prosecution or in prison for illegally using melamine-tainted milk powder, said the State Council's Food Safety Commission here Thursday.

They were found to have used melamine-tainted milk powder as raw material to produce dairy products or sell such dairy products, said a statement issued by the commission.

Among them, 17 had been convicted, including two people sentenced to life in prison, the statement said.

Thirty-eight people were awaiting trial and 41 others were under investigation in police custody, the statement said.

Chinese authorities since July last year have cracked down on the use of undisposed tainted milk powder produced before the melamine scandal of 2008.

About 2,132 tonnes of melamine-tainted milk powder was seized in the latest crackdown, the statement said.

Loopholes in the quality control system of dairy products were identified in the campaign, the statement said.

A total of 191 officials were punished for failing to do their duty, with 26 of them fired, it said.

In July last year, Dongyuan milk powder, produced in west China's Qinghai Province, was found to contain excessive levels of melamine, a toxic chemical normally used in the manufacture of plastics, which triggered the nationwide crackdown.

It is the latest blitz on tainted milk products since 2008 when melamine-tainted milk powder killed at least six infants and sickened 300,000 children across the country.