Labor has seized upon reports of a boat arriving in Darwin, accusing Immigration Minister Scott Morrison of going into hiding on the issue of asylum seekers.
On Wednesday, Channel Nine reported that a boat carrying about 19 people, who are understood to be asylum seekers, arrived in Darwin overnight.
But under a new policy, introduced by the Coalition government, Australian authorities no longer announce when a boat has arrived in Australian waters, and are not able to confirm reports.
It was reported that the group was brought into Fort Hill Wharf in Darwin Harbour before being placed on a bus on Tuesday evening.
''It appears another boat arrived and was taken into Darwin Harbour last night,'' acting Opposition Leader Chris Bowen told reporters in Sydney on Wednesday.
''A boat that Tony Abbott and Scott Morrison don't want us to know about.''
Mr Bowen said that Mr Morrison has gone from criticising boat arrivals in opposition to ''avoiding scrutiny'' on the subject when he was the Immigration Minister.
''Now he's actually the minister responsible for doing something about it, he's gone into hiding. He's in a witness protection program,'' he said. ''It shows that this new government is more interested in managing the media cycle than managing our borders.''
It is unusual for asylum seeker boats to make it as far as Darwin, although Customs reported that a boat was picked up north-west of the city on the day after the federal election.
In a new policy approach, the Coalition has announced that it will not provide individual announcements when a boat arrives in Australian waters - as occurred under the Labor government - but provide weekly updates on Operation Sovereign Borders instead.
Australian authorities have picked up an estimated nine boats carrying asylum seekers since the September 7 election.
Addressing the media on Monday, Mr Morrison said he would not go into tactical or operational details in his planned weekly briefings, including whether a boat had been turned back.
''We are not getting into the tactical discussion of things that happen at sea ... This is an open briefing process but there are obvious limitations to what can be discussed,' he said.
The Greens have argued they will try and use the Senate to force the government to release the information as it happens.