Managers of the Nauru detention centre have been admonished for not answering key questions during an Australian Senate inquiry into sexual abuse and violence at the facility.
The inquiry's first witnesses were from Transfield Services, which won a 1 billion US dollar contract from the Australian government to manage the facility.
A number of questions directed at the company were taken "on notice", meaning they will be answered later, including on how many males and females worked at the centre.
The inquiry's chair, Alex Gallacher, told Transfield's chief executive of operations, Kate Munnings, the lack of knowledge was extraordinary.
KATE MUNNINGS: Senator, we have come on short notice, we are very happy to participate, but we want to give the committee accurate information not guesses.
ALEX GALLACHER: Absolutely. And if you're asked the gender balance of 500 people I find it extraordinary that the three people at the table do not know. So take that on notice that I think that's extraordinary.
The inquiry's chair Alex Gallacher, speaking to Transfield's Kate Munnings.