Federal police have raided the Department of Home Affairs office in Canberra, as officers investigate a leak related to the au pair saga.
A parliamentary inquiry in September heard that the leaking of emails showing Home Affairs Minister Peter Dutton overruled the advice of border authorities to allow a French au pair into the country had been referred the AFP to investigate.
A police vehicle was seen outside the Canberra office on Thursday.
Read Next An AFP spokesman told AAP it had received the Home Affairs leak referral on August 30.
"The matter has been accepted for investigation," the spokesman said.
"The AFP has undertaken enquiries and conducted a number of activities in relation to this investigation."
Labor justice spokeswoman Clare O'Neil said Mr Dutton himself had serious questions to answer over the au pair issue.
"He told us that he didn't have any connection with the two families for whom he gave an au pair arrangement and we know that that ultimately wasn't the case," she said.
"What I don't want to see here is ... the Home Affairs Minister taking action against people who are divulging information that's probably in the public interest, when it's him that has a case to answer."
Comment is being sought from Mr Dutton's office.