Northern Territory Police have confirmed a further 10 travel agencies are being investigated over the potential rorting of a government travel concession scheme.

Attorney-General John Elferink told reporters all the agencies were connected with the Flight Centre travel company.

"We do expect Flight Centre as an organisation to cooperate with the police investigation," Mr Elferink said.

"I've said that it is a matter of policy of this Government that where criminality is suspected, that the matter should be referred to the police."

Mr Elferink said Flight Centre had already repaid the Government almost $2.3 million in relation to the Pensioner and Carer Concession scheme, but stressed that was not an admission of guilt and should be seen separately to the referral to police.

"A settlement of a civil debt, you cannot automatically assume that's evidence of anything that may or may not be in the criminal domain," Mr Elferink said.

The news comes after NT Police raided a Darwin business in relation to the travel scheme, and confirmed in February that five agencies were under investigation for potential rorting.

Last year, former NT Crime Stoppers chairperson Alexandra "Xana" Kamitsis was jailed for rorting the same government travel concession scheme and corruptly giving benefits to a political staffer.

The court found that for a five-year period, Kamitsis invoiced the Health Department for inflated flight costs, purchased cheaper flights for pensioners and kept the extra money.

"What has become apparent through the taskforce process is that business model may have certain similarities between the business models of other criminal matters that have now been established," Mr Elferink said.

A statement from NT Police said no further comment would be made as the recent referral was now under investigation.