Pande Veleski's family said they knew he was unwell but 'never knew it was to this point'

The attack took place at a picnic stop on the Stuart Highway in Australia's Northern Territory. Photo / NewsCorp

The family of the man arrested over the stabbing death of a French tourist in the Australian outback said they knew he was unwell but not "to this point".

Pande Veleski's sister-in-law Mary Veleski said they are "heartbroken" and their hearts go out to the family of the victim, Philippe Jegouzo.

"We're heartbroken, we're in a lot of hard time at the moment. This has never happened to our family."

She said her husband Tony Veleski, Mr Veleski's brother, was "distraught" at the incident.

"We don't know what to do," she told the Northern Territory News. "We knew he was unwell, but we never knew it was to this point. I just feel for everybody."

A man believed to be Pande Veleski, 35-year-old man held in relation to the death of a French tourist in the Northern Territory. Photo / Facebook

Pande Veleski was arrested over the stabbing of Jegouzo, which occurred at Connors Well, 90km north of Alice Springs. Police believe he stabbed the Frenchmen before being found naked in the outback by a police helicopter during a search. He has not been charged.

The attack occurred 200km from where Peter Falconio was murdered in 2001. It's understood his former partner Joanne Lees is back in the area to take part in a 60 Minutes programme documenting her quest to have a memorial built at the site.

The wife of the French tourist has been released from hospital. Earlier, police said she was "traumatised and devastated" by the attack and had not yet given a statement.

Police said the attack was a "random ... obscure event that couldn't have been predicted on any scale".

It's understood the victim's wife was forced to fight off the alleged attacker with a picnic table, before he fled in a silver car. A passing nurse drove by the couple on the roadside and performed CPR as her husband phoneed emergency services, the NT News reports.

Media reports say Veleski's family did not even know he had left Victoria and revealed that he had previously been treated for mental health issues.

NT Police detective superintendent Travis Wurst told media Veleski was currently "not undergoing a mental health assessment".

"The person is in police custody for treatment of exhaustion and dehydration in Alice Springs Hospital," Supt Wurst said.

"He will be taken to the watch house this evening or tomorrow."

"He has not been assessed in relation to his mental health at all," Supt Wurst said. "He has not been interviewed."

Supt Wurst said the victim's wife had experienced something "traumatic and devastating".

"We've offered as much support as we can," he said. "She's crucial to our investigation but we're not rushing our attempts to speak to her and obtain a statement."

"She has support ... she's linked to the French Consulate and other people in Alice Springs.

"She is extremely upset and traumatised by the events she witnessed. This is an absolute tragedy, an absolute random and obscure event ... it could not have been predicted on any scale."

Police are appealing for witnesses or anyone who drove north or south about 100km north of Alice Springs on the Stuart Hwy on Wednesday afternoon to come forward.

They are particularly interested in speaking to any drivers with dashcam who travelled the route - even if they believe their footage to be irrelevant.

"Part of our investigation is to endeavour to find what motive may have led to this occurring," Supt Wurst said.

"That's why we're calling for the public to provide us with any information in relation to events that may have led to this death."

They also want to hear from anyone who may have seen the car being driven by Veleski, a grey Hyundai i20, or the French couple's Red Toyota Rav4 with South Australian numberplates.

Jegouzo, 33, was stabbed in the neck at a roadside rest stop and died on the scene in Aileron, North of Alice Springs, on Wednesday afternoon.

The victim's wife was with him at the time and was treated for shock at the Alice Springs Hospital before being discharged on Thursday night.

When first approached by police after the incident, Veleski, 35, was wearing some clothes but when detained the following morning he was naked, police said. Supt Wurst yesterday said a search of the area had since uncovered some items of clothing believed to belong to the suspect.

Mr Veleski's brother Tony said the family did not know he had left the state and thought the 35-year-old had travelled to the family's holiday house in Dromana, on Victoria's Mornington Peninsula.

Large blood stains were visible at the scene. Photo / NewsCorp

"He came and got my keys. He was supposed to be in Dromana," Tony told Fairfax Media yesterday.

"We were meant to go there today to see him, to spend time with him, me and my son.

"We're really sorry for the French tourist, and we're sorry for my brother as well."

The report said Veleski lived with his mother in Mill Park and had previously been treated for a mental health condition.

After the alleged attack, the victim's wife flagged down another couple in a passing car with a nurse staying at the scene while her husband drove 30km to the nearest telephone at the Aileron Roadhouse to call police. Detectives said the victim's wife was traumatised by the incident and described the attack as unprovoked.

"This is an absolutely devastating occurrence for her and for her family and that of the deceased as well," NT Detective Superintendent Travis Wurst said.