CANBERRA, June 4 (Reuters) - Highly pathogenic avian influenza has been detected at a third poultry farm near Melbourne, but it is not the same strain that has spread globally and raised fears of human transmission, the Victoria state government said on Wednesday.

Hundreds of thousands of birds have already been destroyed after bird flu was found at two Australian egg farms last month.

The third farm is within a few kilometres of the first to report infection and both have the same H7N3 strain of the virus, while the other farm had an H7N9 strain, the state government said.

All three farms have been placed in quarantine with restrictions on movement in surrounding areas.

"The detection of avian influenza at this additional property is not unexpected and is the result of ongoing surveillance activities within the Restricted and Control Areas," said Graeme Cooke, Victoria's chief veterinary officer.

The outbreak poses no risk to consumers of eggs and poultry products, the government said.

Australia has seen nine outbreaks of Highly Pathogenic Avian Influenza (HPAI) since 1976, all of which were contained and stamped out.

In recent years a different strain of bird flu - H5N1 - has swept the globe, killing huge numbers of farmed and wild birds. It has also spread to tens of mammal species and through the U.S. cattle herd and infected three people in the United States and one in Australia.