Hon Hai Precision Industry Co. acknowledged that some student interns worked night shifts and overtime at a production site in northeast China in violation of company policy, the latest hit to the labor practices of the contract manufacturer for Apple Inc. and other electronics companies.

Hon Hai, which uses the trade name Foxconn Technology Group, has been under scrutiny by labor groups for its work practices. The same factory last year admitted to having temporarily hired underage interns.

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