No cause of death has been revealed and it is not being treated as suspicious.
In a statement on Monday, his family said: “We lost our handsome, talented, funny, complicated and beloved Dieter on Saturday morning.
“He has left a massive hole in our lives and our world will never be the same. Our thoughts go out to all of you who knew him, loved him, or worked with him over the years. We appreciate you respecting our privacy at this terrible time.”
Channel Seven said they were "deeply saddened" about the actor's death, in a tribute to Brummer on the Home and Away Instagram page.
"Home and Away and @channel7 are deeply saddened to hear of Dieter Brummer’s passing. Dieter was a much-loved Home and Away cast member and celebrated by Australian and international audiences for his award-winning portrayal of Shane Parrish. We send our sincere condolences to Dieter’s family and friends during this very difficult time," the post read.
The two-time Logie winner was best known for his role as Shane in Home and Away, however he also appeared in Underbelly, Neighbour, Rescue Special Ops and Winner and Losers.
He appeared on Home and Away from 1992-1996, and won the Logie award for most popular actor in 1995 and 1996.
According to the Daily Telegraph in 2020, Dieter was running a window cleaning business in between acting jobs.
He made headlines for his storylines with his on-screen wife, Angel Brooks, who was played by Melissa George on Home and Away.
However, the actor told Woman’s Day that things between them off-screen were a lot different to what audiences were used to seeing on-screen.
“We may have been love interests on the show but the chemistry was far from real,” he said in 2012.
“Mel was incredibly ambitious right from the outset. I think she wanted to be the next Kylie Minogue.
“She was a big fan and she aspired to be a big star just like Kylie. I don’t think she had much time for the cast of Home and Away.”
Melissa George also spoke about their relationship on the 2018 TV special Home and Away: Endless Summer, saying: “There was a lot of pressure on us.
“We had to look like the perfect darling couple in public.”
Entertainment reporter Peter Ford tweeted a tribute to the star, who was known as the ultimate heart-throb of the show.
"Very sad to hear of the death of former TV heart-throb & Logie winner Dieter Brummer at 45 years old. Home & Away was a massive hit for him in the 90s. There were other credits too but when you hit such dizzying heights at a very young age life & career after can be problematic," he wrote.
Fans reacted to the sad news, with one person writing: "So terribly sad. As a teenager I had his poster on my wall."
"Very shocked and saddened to hear this. I worked with him on Underbelly 3, and he was good across the whole season, but delivered a particularly fine, and criminally underrated performance in one of my episodes. A real loss," another said.
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