Devastated family members of Renee Duckmanton, whose body was burned and dumped on a rural Canterbury road, didn't know she had been sex worker until police told them.

Police have stepped up their presence in Christchurch's red light district after the 22-year-old's burnt body was found on the roadside verge of Main Rakaia Rd, 500m from State Highway 1, by a member of the public driving past at 7.40pm on Sunday.

Detective Inspector Darryl Sweeney said police are investigating whether Ms Duckmanton's involvement in the sex industry is connected to her death.

"We do, however, have to remember that Renee is first and foremost a daughter, a sister, and a much-loved member of a family, and police will continue to work tirelessly to bring this to a resolution," he said.

A homicide investigation is underway after the woman's body was found on Main Rakaia Rd, 500m from State Highway One, by a member of the public driving past at about 7.40pm on Sunday. The victim has been named by police as 22 year old Renee Duckmanton.

Several members of her family were in the dark over her choice of job.

Ms Duckmanton's cousin Tracey Lee McGrath, 40, wasn't aware she was a sex worker until police told the family. "It's a job. We love her for her," she said today.

She described Ms Duckmanton as a "really bubbly, really happy, a lovely girl".

"We are all devastated. It doesn't feel real," she said.

"She was pretty much a kid herself. Even though she was 22, she was still young."

Father Brent McGrath told the Herald he was "very, very devastated" at the loss of his "adorable" daughter.

A spokeswoman for the Prostitutes Collective said sex workers in Christchurch were on edge.

Ms Duckmanton's killing is the fourth such slaying of a sex worker connected to Christchurch in recent years.

Police at the house on Bowenvale Avenue where Renee Duckmanton lived. Photo / Kurt Bayer
Police at the house on Bowenvale Avenue where Renee Duckmanton lived. Photo / Kurt Bayer

Today, detectives, specialist police staff, and forensic experts are concentrating on the Christchurch house where Ms Duckmanton had been living.

The back-section weatherboard house at Bowenvale Ave in the suburb of Cashmere, with sleepout nestled in the corner of the well-kept property, was cordoned off yesterday afternoon.

Since then it has been a hive of police activity, neighbours say.

One elderly neighbour said there were a lot of "undesirables" coming and going from the house, often late at night.

Ms Duckmanton's mother Tracy's Housing New Zealand house at nearby Kowhai Tce, St Martins, has also been closely looked at by police.

It remains cordoned off today, with a police car parked outside.

Flowers in tribute to Ms Duckmanton have been left outside the house.

Her body was found in a rural area where several suspicious fires had been lit on Sunday.

Police originally thought the fires and the homicide could have been linked, but have since ruled out any connection.

Local dairy farmer Michael Norton has reported to police the theft of two 20-litre containers of petrol from his farm on Main Rakaia Rd on Saturday night.

Kirwee Volunteer Fire Brigade were rushing to reports of a scrub fire when they found Ms Duckmanton's body on Sunday evening.

"They extinguished the grass fire and protected the scene for police," said Rakaia Volunteer Fire Brigade station officer Tyrone Burrowes.

Mr Sweeney said Ms Duckmanton died an "unlawful death" and had been burned.

Anna Reid, of the Prostitutes Collective, which supports the rights, health and well-being of sex workers, said Ms Duckmanton's death would be making other people in the industry feel vulnerable.

She said Ms Duckmanton was known to the collective, but had never sought its help.

She said the collective would be out on Christchurch's streets tonight talking to sex workers, adding that police would be stepping up their presence as well.

Ms Duckmanton's death will revive painful memories for sex workers in the city.

In April 2005, prostitute Susie Sutherland was strangled to death, and in December that year another sex worker, who has permanent name suppression, was repeatedly run over by a man before her body was dumped in the Avon River.

In 2008, prostitute Mellory Manning was killed over a drug debt she had with a Mongrel Mob member.