The BBC's Annie Gardner: Police are expecting the death toll to rise

Detective Superintendent Paul Schramm said the body was found about 10ft below ground and roughly beneath the body previously discovered in the garden.

He said: "It certainly indicates the body had been in the ground for some considerable time."

Parts of eight other bodies were found in barrels containing acid in an abandoned bank vault in Snowtown, 90 miles (150km) north of Adelaide, last Friday.

Police believe the body of one more missing person is still to be found.

But Det Supt Schramm said he did not expect to find that body in the grounds of the house where the other remains were recovered.

Three men from Adelaide have been arrested in connection with the macabre discoveries.

Possible motives

Police found badly decomposed remains in bank vault vats

Police said all the victims had been on missing persons lists, and they were investigating possible links between the murders and social security fraud.

Some of the missing persons benefits were being collected until quite recently.

However, police say they have not yet established a common link between all the victims, because some of them were not recipients of social security payments.

One of the victims is thought to be the 37-year-old wife of one of the accused, Mark Haydon, 40.

The other two suspects are John Bunning, 32, and Robert Wagner, 28.

Another victim is thought to be Barry Lane, a convicted paedophile and transvestite, who allegedly had a long affair with Mr Wagner. A third could be a drifter called Clinton Trezize, who has been missing since 1993.

Police are playing down any suggestion of a sexual motive in the case.

"Drugs, organised crime, paedophilia and sex-related things are certainly not the focus of investigations," said Det Supt Schramm, who is heading the 33-strong police task force investigating the case.

Acid vats

Police broke into the bank in Snowtown on Friday. It closed around two-and-a-half years ago. Since then it had been rented by a woman who sold plants and crafts.

Victim number nine was found buried in a garden

Constable Ian Young, of Snowtown police, said the murders were believed to have taken place elsewhere and the bodies subsequently brought to the town.

"From what I understand there was no person involved in those murders from within Snowtown or the surrounding district," he said.

"They were murdered elsewhere and the drums were brought to Snowtown because it was a quiet little town and there was a premises ideal for the persons involved."