A man has told a Queensland court it was routine for several persons of interest in the murders of two Sydney nurses in the 1970s to abduct and bash women.

Lorraine Wilson, 20, and Wendy Evans, 18, were hitchhiking across south-east Queensland in 1974.

They were killed at Murphy's Creek in the Toowoomba ranges and their bodies were found two years later.

No-one has been charged over the crime.

Seven people have been named as possible suspects in the murders.

Four have died, but two testified today at the third day of the hearing in Toowoomba.

Terrence James O'Neill and Allan "Unnie" Laurie answered "no" or "I don't remember" to most questions.

The counsel assisting the coroner, Craig Chowdhury, questioned how the men could have such little knowledge of the well-publicised case and were only aware of their suspected involvement when they were summoned to a CMC hearing in 2010.

During heated exchanges with Mr Chowdhury, O'Neill played down his association with two other persons of interest in the case.

O'Neill flatly denied any involvement in the crime, answering most questions with a simple "no".

As he left the witness stand he told the victims' families who were present in court that he was sorry for their loss but did not know who killed the women.

Meanwhile, Trevor Hilton, who is related to several men named as persons of interest in the murders, told the Coroner's Court he knew nothing about the murders until a police officer quizzed him about the crimes in 1988.

Mr Hilton says he was in jail when the murders were committed.

However, he says it was not unusual for the persons of interest to bash and abduct women in Toowoomba.

ABC reporter Leonie Mellor said the court was told:

They used to stop in the street in Toowoomba on any given night, pull girls into the car, violently bash them, brutalise them, punch them ... punch them in the stomach, even raping them.

Apparently their reputation was very widely known, even so, police did never arrest them.

Another witness, Anthony Dougherty, testified this morning that he saw two women fitting the description of the pair get into a car with a man in the Brisbane suburb of Oxley in October 1974.

He says the car was a pale green Holden that has been linked to three surviving persons of interest in the case.

Other witnesses have testified about seeing the women in the same car, but all the sightings were on the Toowoomba range.

The court heard evidence on Monday from a former police officer who said that if one person of interest, Wayne Hilton, had been still alive, he would have had him arrested and charged with the murders.