Subhakanta Behera, 50, collapsed and fell unconscious on Friday evening after exercising on the treadmill at home in Melbourne, Consul Rakesh Kawra told Fairfax. "It's a very sad moment for us," he said, saying his former boss had previously been posted with the Indian foreign service in Washington and Moscow.

Dr Behera's 21-year-old son, Ananya, an engineering student at Monash University, posted on Twitter that his father had died of a heart attack: "Rest in Peace Papa," he wrote.

''At this critical juncture in my life all I can really say is - 'Life is not measured by the number of breaths you take, but by the moments that take your breath away!'

"I'd like to thank everyone - family, friends, relatives, neighbours - for their undying support and condolence messages. I hope my father is out there in spirit watching over me and giving me the resolute strength to take care of my family."

Dr Behera is also survived by his daughter Amruta and wife Rajashree.

Mr Kawra said paramedics arrived "very quickly" but were unable to revive Dr Behera. He described his former boss as a "simple, down-to-earth" man who was passionate about his work.

At a speech Dr Behera gave last year in Melbourne on Gandhi, he said the spiritual leader's teachings ''will continue to inspire generation after generation to seek solution in eternal principles of non-violence, truth and peace, while helping to create a more meaningful, purpose-driven, self-aware and socially responsible life. And I have robust optimism that in such an enlightened life lies the panacea for a multicultural, multi-ethnic, harmonious order."

Premier Ted Baillieu and Minister for Multicultural Affairs and Citizenship Nicholas Kotsiras said in a statement: "Dr Behera was a proud, passionate and very effective representative of the Indian community, and a great friend of Victoria.

"The Victorian Government will assist the family in any way possible during this difficult time."

The memorial service will be held at the Indian Consulate, 344 St Kilda Road, from 2pm