Members of the family of the 70-year-old man identified as Christos Pittas from Greensborough have joined volunteers in the search for their father who went missing last Friday while on a walk at Dinner Plain near Mount Hotham.

As conditions have become colder with snow forecasted, concerns have deepened for Mr Pittas since he was last seen at Big Muster Drive on Friday afternoon. He was believed to have gone in search of emus that had been seen in the area.

When he went on his walk Mr Pittas was dressed in a long-sleeve top and jumper, long pants and crocs but with the weather becoming increasingly cold, the fears for his welfare have grown. His daughter Elia Bird, in a Facebook post on Sunday, expressed concern that time was running out for her father.

“We assume he got lost of one of the many hiking trails and perhaps injured himself. … (he is) poorly dressed in the wild terrain. … Time is against us with the snow coming on Monday,” wrote Ms Bird.

Christos Pittas in a photo pasted by his daughter (identity of the child obscured). Photo: Facebook/Elia Bird

In a statement quoted by the ABC, the missing man’s family thanked the volunteers for their work and said they were praying for his safe return.

“We are devastated knowing that our dad, Christos, is still missing in Mount Hotham’s high country,” the family said. He is a grandfather to four beautiful granddaughters and we know he would love to see them again,” the family said in the statement.

Victoria Police Inspector Paul Hargreaves was reported as saying: “A couple of his sons, his daughter and a few others are out today helping them search…. We’ve got a police member with them and they’ve gone out to a few areas thinking, ‘Where would dad go, what would he do?'”

Inspector Hargreaves said on Monday that 140 emergency workers were involved in the search with support from Parks Victoria, the State Emergency Service (SES) and Bush Search and Rescue combing track and off-track areas.

Acting Sergeant Joel Magno-Thornton of the Police Search and Rescue Squad said conditions have been worsening since Mr Pittas was last seen at 2.45pm on Friday, 13 May.

“The temperature has dropped 10 degrees Celsius since the search started. It is cold and the wind chill is about -12C. For our searchers to be out there, we are actually putting some of them in harm’s way themselves. We have got to be very mindful of where we’re putting our people.”

Image of the missing Christos Pittas released by Victoria Police. Photo: Supplied

State Emergency Service (SES) Commander Josephine Hunter said the most experienced alpine searchers were involved in the hunt for Mr Pittas.

“Because of the conditions and the terrain we’ve put some of our most experienced and skilled searchers out there. Obviously they’re battling the conditions as well as a number of obstacles in the field,” Commander Hunter was reported as saying.

According to nine.com.au, Inspector Hargreaves said that there was still ” a very high chance” that Christos could be alive if he was close to a source of water and was sheltered from the wind. but added that the fact he had not yet been found suggested that he could have fallen or got into trouble