Police suspended the search for the 45-year-old on Saturday after he fell overboard the Spirit of Tasmania at about 11.40pm on Friday night.

It’s still unknown how the man ended up in the water, with various media reports stating that he either fell, or jumped off the ship about 124 kilometres south-east of Port Phillip Heads.

Police have found clothing and other items believed to have belonged to the man.  

Spirit of Tasmania I was travelling from Melbourne to Tasmania at the time of the incident, which sparked a massive search of a 247 square kilometre area.

The Australian Maritime Safety Authority was notified at 12.10am on Saturday morning and coordinated the search with two helicopters, including the Victoria Police Air Wing, along with Spirit of Tasmania ferries and two cargo ships.

Water Police, four helicopters and the maritime authority's dedicated search and rescue plane joined the search from first light.

However, the plane arrived back in Melbourne shortly after 1pm on Saturday without locating the man.

A spokeswoman for the maritime authority confirmed the search had been suspended. 

The spokeswoman said the decision to suspend the search was based on expert medical advice that the man could not have survived past midday (on Saturday), taking into account various factors including water temperature and weather conditions.

►Support is available for anyone with a mental illness by visiting Headspace, phoning Lifeline at 13 11 14 or the Kids Help Line at 1800 55 1800, Reachout and BeyondBlue