Former Beauty and the Geek winner Kiera Johnstone has been forced to publicly deny rumours wrongly linking her to a grisly alleged murder.

An ex-castmate of the reality program, who cannot be named for legal reasons, is accused of killing her partner after a man’s body was found inside a property in Port Lincoln, South Australia following a fire on Thursday.

The accused was taken into custody at the scene but a court order has been placed over her identity and details of the case.

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Johnstone said the rumour mill had gone into overdrive and took to social media at the weekend to declare she had not been arrested last week and was “not involved in any way” to the alleged crime.

“There has been speculation online suggesting that I am involved,” she shared on Instagram.

“Let me be absolutely clear: I have never been charged with a crime.

“The allegations being discussed have nothing to do with me, and the fact that I even need to say this is incredibly upsetting.”

Johnstone — who won the 2021 series of Beauty and the Geek alongside her match Lachlan Mansell — said the online speculation was being fuelled by people “sharing, gossiping, or silently watching”, and asked for it to “please stop” given it is “a serious situation”.

“It’s deeply disturbing to see people spreading false information, making assumptions and sharing screenshots,” the Melbourne jewellery boutique owner said.

“This kind of speculation is damaging and invasive and is something I take very seriously.”

Police and forensics spent significant time at the Port Lincoln property after a man’s body was discovered on Thursday afternoon.

The accused — who also appeared on Beauty and the Geek, a program where socially awkward men share a mansion with attractive women — was arrested at the scene and taken to a local hospital, where she was charged with murder.

“I don’t have any advice in relation to how long the man has been deceased. That will form part of our investigation,” SA Police State Operations Service Assistant Commissioner Ian Parrott said on Friday.

“I’m not going to comment on the injuries of the deceased.”

The accused faced court on Friday via phone link and has been remanded in custody.

She will appear in court again at a later date.