A man accused of the kidnap and murder of a Hamilton woman was seen by witnesses strangling her to death and hiding her body, the Crown says.

Rae Portman, 33, was four months pregnant when she went missing in June last year. Her body was discovered covered in rubbish bags in a pit on an Ardmore farm, near Auckland, three months later.

Paraire Te Awa, known as 'Friday', and Dean Michael Addison have both pleaded not guilty to charges related to her death.

Te Awa has been charged with the murder and kidnap of the Hamilton woman, while Addison faces a charge of kidnap and two drugs offences.

A third man, Lee Rigby, was jailed earlier this year for his involvement in the kidnap.

The trial at Auckland High Court began this morning, where the jury heard that Ms Portman was involved in transporting a pre-cursor substance in the manufacture of methamphetamine.

She was to find and deliver it to someone who would turn it into 'P', for which she would receive an ounce of the drug with a street value of around $14,000.

The Crown alleges she had delivered a package of the pseudoephedrine - also known as a 'set' - to Addison, who had failed to either turn it into drugs or pay her. When she pressured him for payment, he decided to deal with the "problem" and "teach her a lesson".

The plan was to kidnap and scare her, but Te Awa "took things into his own hands" and strangled her to death in an industrial site in Hamilton, before dumping her body in a pit at a friends farm on the Papakura-Clevedon Road, Crown counsel Anna Pollett said.

The Crown alleges Addison knew Ms Portman was going to his house on the night of June 20 to demand he pay for the pseudoephedrine or give the package back, and hatched a plan to kidnap her.

However, he was not aware that night that Te Awa killed her, Ms Pollett said.

"There was no mention of what Te Awa had actually done to Rae Portman, and instead he told Dean Addison that he had let her go and told her to go far away and never make contact with them again," she told the court.

Rigby, who drove Ms Portman's car to Hamilton with her bound and gagged in the boot, is due to testify on behalf of the Crown saying he saw Te Awa tie a noose around Ms Portman's neck and twist it until she died.

He will also tell the court that Te Awa "bragged about her [Ms Portman] being in the back of [his] yellow ute for a couple of days", Ms Pollett said.

A former boyfriend of Te Awa will give evidence saying he saw the accused handling the body of a blonde-haired woman, she said.

He had travelled to the Ardmore farm with Te Awa, and despite being told to stay inside, saw his then partner down the side of a shed holding something in a blue and white plastic sheet.

"What he saw was a pale face and blonde hair. He could tell it was a body of a female," Ms Pollett told the jury.

Crown evidence includes phone and text message records which place Te Awa at the scene and show discussions between him and Addison, and a receipt showing Te Awa took Ms Portman's black Mazda to a scrap yard in Hamilton.

Despite having little forensic evidence to present to the court, the Crown said a fingerprint matching Te Awa's was found on a piece of paper inside Ms Portman's handbag, which was found in a shed on the Ardmore farm.

The trial continues tomorrow, when the defence counsel for both of the accused will begin their opening statements.

- APNZ