if u know the name of a person against u are to cpmplain, u can visit directly to Ministry of External Affairs website... thee u will get various email addresses of secretary level to Minister... write a coplain and cc mark to all the addresses u get including te president and prime minister... within 10 days ur purpose will besolved.. but their shud be some valid reason against camplaint
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A similar thing happened to me , but it wasn't by the embassy, but in the airport. In my case, I just approached the Airport GM and spoke to him, and to my pleasent surprise, the staffer who harassed me got railed right there in public. I don't know how embassies work, I have never had a bad exp in a CHinese embassy in HK.
The Chinese are pretty strict about professionalism these days. Indians who can afford international travel are considered a valuable market in China, either in the investment or tourism fields. The Europeans and the Americans are already standardized in that regard, but the Chinese are really pushing forth aggressively.
The Chinese value you as a valuable investment. Use that to your advantage. Good luck and sorry about your harassment. But try and get in touch with the superior of whoever harassed you and action should be taken before you can say "vodka shot."