Proof of Death (hospital Death summary or medical Certificate of cause of Death).
Identity proof of the deceased (Aadhaar, passport, etc).
Identity proof of the applicant.
Proof of relationship with the deceased (if applicable).
Proof of residence of the deceased (Aadhaar, utility bills, etc).
Cremation or burial certificate (from the crematorium or burial ground).
Authorization letter (if someone else is applying on behalf of the NRI).