The Sûreté du Québec is looking for a 42-year-old woman, wanted for kidnapping her three children back in April.
Police believe Yanna Mavraganis and her kids could be staying at women's shelters in Ontario.
The children are Maximos Finley-Mavraganis, 8, Maya Finley-Mavraganis, 8, and Marina Finley-Mavraganis, 5.
Police say Mavraganis may be driving a dark blue Toyota Matrix, with the Quebec licence plate G32 JME.
The Sûreté du Québec took over this file from the Gatineau Police Service last month.
It has issued an arrest warrant for Mavraganis, and say the children must be handed over to the father, who lives in Quebec, in accordance with a custody order.