A man with 'multiple' stab wounds to his torso presented to the Launceston General Hospital on Saturday morning.
Tasmania Police is also looking into a disturbance in the CBD about 9.30pm on Friday night.
About 2.30am, a 38-year-old man came into the hospital wearing blue jeans and a white Unit t-shirt with black writing.
The man has brown hair and is about 180 centimetres tall.
Tasmanian Police is urging the man, or anyone with information to come forward.
Police have not been able to speak to the man to find out what occurred.
However, they are also requesting public assistance about a disturbance in Wellington Street and the central business district between 9.30pm on Friday and 2.30am on Saturday.
A man matching the description of the wounded is believed be to involved.
Information can be provided anonymously by calling Crime Stoppers on 1800 333 000 or online at crimestopperstas.com.au. Launceston Police station can also be contacted on 131444.
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