His father and brother were also arrested in the days that followed.
“The man is believed to have travelled to Slovenia several times in his car. He could not be contacted by the investigating police,” a November 26 press release stated.
He was located following reports of a car burning in a Šentilj casino carpark close to the border with Austria.
Reports suggest he did not explain how his red Volkswagen had caught alight.
Several suspicious details of Pieper’s final hours had already been reported by the Daily Mail.
On the morning of her disappearance, Pieper allegedly texted friends about a “creep in the stairwell” of her Graz apartment building.
The photographer she was set to meet ran into her ex-partner at the scene soon after, alerting police when he discovered Pieper’s dog alone in her home.
Her switched-off phone was then discovered in nearby bushes by responding officers.
Austrian authorities have requested the man be extradited home as the investigation continues.
