They include an allegation that a security officer used "excessive force" to remove a minor from a bus and separate alleged incidents where officers pushed or threw rocks at child asylum seekers, or touched them inappropriately. In October last year, a child detainee alleged he was raped by another minor in the shower. He was transferred to Australia for medical treatment. Transfield Services said it had received 33 sexual assault and rape allegations: 15 against staff and 18 against detainees. The company also addressed allegations aired previously, including that a local officer gave additional shower time if an asylum seeker exposed themselves, and that contraband was being exchanged for sexual favours – claims mostly made against staff. The allegations were reported to police. Transfield Services said between September 2012 and April this year, asylum seekers had made 253 self-harm attempts. Ten were deemed critical.

The firm also confirmed allegations that tents housing asylum seekers and staff are riddled with mould. It said humidity was often greater than 85 per cent and temperatures frequently hovered around 35 degrees, adding "eliminating the presence of mould has posed an ongoing challenge". The Department of Immigration and Border Protection said in the two years to May this year, 355 detainees at Nauru were prescribed psychotropic drugs, including antidepressants. The evidence follows the independent Moss review into sexual abuse at the Nauru detention centre, released in March, which found evidence of rape, sexual assault of minors and guards trading marijuana for sexual favours from female detainees. Departmental evidence to a separate Senate inquiry this week revealed that the Commonwealth has paid three so-called "illegal maritime arrivals" a total $385,000 compensation for psychological injury allegedly suffered in immigration detention.

The cases were among 74 claims for compensation from asylum seekers in the past five years, the majority of which claimed personal injury. Of those, 58 claims are still before the courts and nine were resolved prior to hearing because the Commonwealth was not legally liable, or for other reasons. The Australian Lawyers Alliance has previously warned Australia could be liable for a "swathe of future compensation claims" due to its offshore processing regime. As Fairfax Media reported on Friday, more asylum seekers have died at Manus Island than have been resettled. In its submission to the Nauru inquiry, the department said service providers "ensure that the welfare and safety needs of the alleged victim are addressed in a timely manner" following an assault allegation.

It accepted all 19 recommendations of the Moss review and has developed a "comprehensive action plan" to implement them, in conjunction with the Nauruan government. "The government of Nauru and the department are working with service providers to strengthen existing procedures for the personal safety and privacy of transferees," it said. Transfield Services' submitted policies "are designed to support the safety and security of the centre, the welfare and wellbeing of transferees" and detainees are treated "fairly and with dignity and respect at all times". Wilson Security said its service at Nauru "supports the wellbeing of asylum seekers and minimises harm". The department and Transfield Services have been contacted for additional comment. Wilson Security declined to comment.

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