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Twenty-five premises across five states, including the metros of Delhi, Mumbai, Bengaluru and Kolkata, are being raided by the Department.
The premises of Xiaomi and Oppo's executives also being searched by Income Tax officials, sources said.
Officials said the search operation has been initiated after information of tax evasion.
In a statement, Xiaomi said: "As a responsible company, we give paramount importance to ensuring that we are compliant with all Indian laws. As an invested partner in India, we are fully cooperating with authorities to ensure they have all the required information."
In August, Chinese government-controlled telecom vendor ZTE was searched. Searches were conducted at five premises of ZTE, including their corporate office, the residence of the foreign director, the residence of the company secretary, the account person and the cash handler of the company.
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