JacobusMarinus van Nierop, 50, made the admission during an Immigration and Refugee Board of Canada (IRB) detention review hearing on Friday morning via teleconference.
"His statement was … he thought they would want him to return to his country, which is the Netherlands, because he murdered his wife there in 2006," said spokesman Charles Hawkins.
"And no one has any information about that other than he admitted that," he said.
Van Nierop, who was arrested in the town of Nackawic, N.B., on Monday, will remain detained pending his removal from Canada on several grounds. Hawkins said the grounds include that he is:- Considered a danger to himself and others.
- A fugitive from justice in France.
- A flight risk.
In addition, Van Nierop has no status in Canada, no fixed address and no financial resources, Hawkins said.
Van Nierop, who is also known as Mark, is entitled to another detention review hearing within seven days.
He had been wanted in France since December on charges of violence causing mutilation or permanent disability and fraud after he allegedly pierced some patients' jaws with poorly placed implants, left parts of dental tools lodged in other patients' gums, and pulled out healthy teeth, Europe 1 radio has reported.
None of the allegations has been proven in court.
Van Nierop participated in the detention review hearing by telephone from the Southwest Nova Scotia Correctional Facility, where he is currently detained.
Canada Border Services Agency officials in Halifax were also on the call, while the IRB decision maker was in Montreal.
Van Nierop was arrested at an apartment building in Nackawic, where he had been living in for the past eight months, according to people in the community CBC News spoke to on Thursday.
He had been practising in Château-Chinon in the Burgundy region of France since 2008.
Local police started an investigation in May 2013, following numerous complaints from patients.
Nicole Martin, president of an association that represents van Nierop's alleged victims, says about 120 people were maimed by van Nierop's dodgy dentistry.
Of those, about 60 people were seriously injured, she said.