One of the detainees, Dhamith Caldera, told AFP that he would "complain to the UN" over his treatment by Australian customs authorities and denied that he had been screened as a possible asylum seeker.
"They never asked any questions. They just wanted us to go back," he said, declining to answer if he believed he had a case for asylum. "They treated us very badly."
He said that they had been given food past its expiry date and people had not been given medicine.
"When women were down with fever, they were just given water," he added. "We were starved. Where is Australia's human rights?"
The group arrived in the late morning by bus and were escorted by plain-clothed police officers after spending a night in the notorious Boossa detention centre.
The complex has earned a reputation for its tough conditions and is used as a high security centre for those jailed on terrorism-related offences.Four women in the group, one of them carrying a baby that appeared to be only a few months old, covered their faces as they passed in front of reporters ahead of their appearance before a magistrate.