Police investigating fake Greens Facebook post praising Martin Place gunman

A fake Facebook post about the Sydney siege, under the name of Greens Senator Sarah Hanson-Young is being investigated by the Australian Federal

Senator Hanson-Young has referred the fabricated post circulating on Facebook to the Australian Federal Police.

The fake post has been copied off Senator Hanson-Young's December 16 statement on the social media site expressing sympathy for siege victims Tori Johnson and Katrina Dawson.

In the original post, the senator calls on the nation to unite following the tragedy and commends police and emergency services for their work on the 16-hour siege.

But the photoshopped version veers away sharply, blaming the government and racism for the outcome.

"The ultimate victim here was Man Haron Monis," the fake post reads.

Senator Hanson-Young said it was disappointing her statement was altered in "such a sinister way" to politicise the tragic event.

"My thoughts remain with the victims and their families," she said.