A brazen thief has been captured on video appearing to steal flowers from a Bourke Street Mall memorial, two days after the horror CBD massacre, which killed at least five people.

The clip shows a man with a bouquet of flowers in his hand, walking away from the shrine where mourners have left flowers and cards for the victims.

He boards a tram, and the video cuts. A second clip shows two police officers escorting him from the tram.

View photos A man can be seen approaching a shrine at Bourke Street, Melbourne, where people have placed flowers for the victims. Picture: Joshua John Arnott More

View photos The man boards a tram with flowers in his hand, before being escorted off by police and made to return the boquet. Pictures: Joshua John Arnott More

The trio can be seen walking back along Bourke Street, before the man places the flowers on the footpath of the mall.

He can be seen exchanging words with the officers before the footage ends.

The video was recorded by Victorian man Joshua John Arnott early on Sunday morning.

The young man told 7 News he was waiting for a mate in the city about 8am when he noticed a man helping himself to the flowers placed at the memorial across the street.

View photos Many Victorians have laid floral tributes at Bourke Street at the scene of the rampage. Photo: Getty Images More

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"I heard a woman yell out 'put them down'," Mr Arnott told 7 News.

"So then I looked up and a guy had a bunch if flowers [in his hand].

"The she started really screaming 'put them down!'. So he just tossed them in the middle like it was trash.

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