A China unit of U.S. tech giant Apple Inc underpaid taxes in 2013 by 452 million yuan ($71 million), according to a report from the country's finance ministry, which comes as China toughens its stance on tax payments by foreign firms. The Ministry of Finance (MOF) report, dated Sept. 9 but cited by official news agency Xinhua on Thursday, said Apple Computer Trading (Shanghai) Co Ltd had already repaid the taxes as well as paying 65 million yuan in late fees. The investigation, however, underlines an increasingly hard stance being taken by Beijing against foreign firms underpaying taxes after authorities said in December last year that they would crack down on the practice. Apple officials in China did not respond to phoned and emailed requests for comment. The finance ministry report said the Apple subsidiary had understated its revenues by 8.8 billion yuan and its costs by 3.4 billion yuan. It had also overstated its profits by 5.4 billion yuan. China levied around $140 million in back taxes from Microsoft Corp at the end of last year.