The federal government has rejected claims by a key crossbench senator that a deal to get asylum seekers off Nauru has led to high-risk offenders entering Australia.

Independent Jacqui Lambie said she was told in a private briefing before the last election in May 2022 that up to 70 asylum seekers were deemed to be high risk. 

Home affairs department officials said 13 people remained on the island nation as of September after a boat carrying 11 people was intercepted that month. 

“A little birdie told me the other day in the last six months the government of the day has been slowly moving them out in the darkness of the night and sending them to Victoria,” Senator Lambie alleged at a parliamentary hearing on Monday.

Senator Lambie made a deal with former prime minister Scott Morrison to get asylum seekers off Nauru and Manus Island, unless they were a security risk, in exchange for her voting with the then coalition government to scrap laws making it easier to bring sick refugees to Australia for treatment.

The department’s acting boss said no one with security concerns or terrorist links had been allowed into Australia for a temporary purpose, after Senator Lambie asked if any had links to Hamas.

“I understand Senator Lambie may have been informed that there was some amongst the cohort who had character concerns – that’s a much broader definition,” department secretary Stephanie Foster said. 

“The ministerial intervention process allows consideration for management in Australia for individuals with character issues, including keeping them in held detention.

“Some of these, of course, may have been resettled in third countries.”

Cabinet minister Murray Watt said it was important any accusations have substantial evidence to back them up in a politically charged environment. 

“If you’re going to suggest that terrorist sympathisers are entering Australia that is a very big call to make at a time where the community is really worried, understandably, around the Middle East conflict and we’re seeing a lot of tension within the community,” he said. 

Department assistant secretary Michael Thomas said people getting off the island were a mix of resettlements and those who had temporarily come to Australia. 

People can be brought to Australia temporarily for medical treatment or before they are resettled in a third country.

When a person is brought to Australia from Nauru they are placed in detention as an unlawful non-citizen and remain there until the minister intervenes.

“A risk assessment process is undertaken at that point to make a determination about the best placement for them,” Mr Thomas said.

A number of people had been resettled in third countries but it was hard to say whether they were the individuals being referred to “without knowing the exact number you’re talking about”, he said.

Senator Lambie said it was made “very, very clear to me there were high-risk people on Nauru that were never going to get off because their own countries won’t take them back”.

“So where are they?”

Officials pledged to provide information on notice about how many people were considered high risk and where those people were resettled.