Sgt. Helene Nepton said authorities are searching the Saint-Apollinaire area on foot with the help of dog handlers, ATVs, and Wildlife Department officers in the search for Martin Carpentier.
Cabin and outbuilding owners are being asked to call 911 to facilitate police searches.
“The goal of this deployment is to search for new hints and secure properties,” the force said in a Twitter message.
The 44-year-old suspects two daughters, Norah and Romy Carpentier, aged 11 and 6, were found dead Saturday following an Amber Alert.
Nepton said the search has intensified since police reported Thursday Carpentier had allegedly stolen items from a trailer within the search perimeter.
Police believe Carpentier may be desperate and try to enter barns, trailers and cabins looking for materials to help him survive.
Owners are asked to have a police escort to search their buildings, but Nepton said theres no indication Carpentier is violent or poses a danger to the public.
Nine days into the search, she said theres also a chance he is unconscious or dead.