Water Minister Tim Holding has gone missing in freezing conditions on Mount Feathertop.
Police are coordinating a search for Mr Holding, who failed to return from a hike yesterday.
The 37-year-old went for a hike on the mountain alone on Saturday and sent a text message to his partner at 6.30pm to say he had arrived at Federation Hut and was expected to be home at 4pm yesterday.
Mr Holding - who holds portfolios in water, tourism, and finance - has been unable to be contacted after this time as his phone is "inactive''.
The alarm was raised at 9.30pm last night when resort management confirmed Mr Holding's car remained at the base of the mountain.
A search crew consisting of a police member and three SES volunteers was deployed to check the hut around midnight.
Walking in snowy, wet sub-zero conditions, the crew reached the hut at 5am today. Mr Holding was not there.
Search and rescue police who have travelled from Melbourne began to search the lower ground of Mt Feathertop at first light while the first crew will explore the area around the hut. A police helicopter will also join the search, weather permitting.
A civilian bush-walking group is expected to arrive at the mountain around lunchtime to join in the search.
Mr Holding is thought to be equipped for the weather conditions, with warm clothes and a tent.
Premier John Brumby said Mr Holding was an experienced hiker, who had hiked in that area previously.
"I am concerned for Tim’s welfare, but I know he is an experienced hiker and was well equipped for the conditions," Mr Brumby said.
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