"An Australian Federal Police officer has been sent to the home country of Gold Coast-based Dr Haneef," Federal Attorney-General Philip Ruddock said.
"I welcome the cooperation that has been provided to the Australian Federal Police," ABC quoted him as saying.
Police custody of the Indian doctor was extended till Wednesday by a Brisbane court.
Haneef, 27, has been in detention for more than a week without charge in connection with the investigation.