Originally Posted by
GUWonder
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The Indian government doesn't always or even generally know if an applicant for an Indian visa has a Pakistani passport when the applicant is using a non-Pakistani passport.
In practice the Indian government does quite often issue Indian visas on non-Pakistani passports of dual-national Pakistanis who neither declare nor appear to necessarily have (or have had) Pakistani nationality.
If a Pakistani enters Pakistan on his Pakistani passport and leaves Pakistan, say, for UK on his British passport, the British passport will contain an exit stamp from Pakistan but no entry stamp. This is how the Indian Embassy staff recognises a dual citizen. I know of at least one person who was refused an Indian visa on his UK passport but offered one on his Pakistani passport (which happens to be much cheaper 65 pence vs 30 pounds at the time).