A search is scheduled to resume Wednesday morning for a three-year-old autistic boy who went missing near Montreal on Sunday.

The search for Adam Benhamama focused Tuesday on an icy river in Laval, Que.

Police say they do not expect to find him alive at this point.

Adam, who cannot hear or speak, has not been seen since Sunday afternoon, and police now believe he fell into the Mille-Îles River.

Adam, 3, has been missing since Sunday afternoon. (Laval police)

"In our minds, we are searching for a body," said Laval Const. Nathalie Lorrain. "We don't think we will be finding the little boy alive, unfortunately."

Adam was last seen on Pointe-aux-Ormes Street in Laval's Auteuil neighbourhood , where he and his family were visiting friends. The home is in a remote section of Laval, metres from the river and the wooded area.

Adam's autism and his inability to hear or speak have complicated search efforts.

"The biggest concern is that he cannot hear us and cannot respond to our signs," Laval Const. Simon Charette said earlier in the search.

Police divers searched the river Tuesday and firefighters worked to break the ice along the shoreline.

Sniffer dogs, all-terrain vehicles and foot patrollers searched neighbouring woods all day Monday but did not find any evidence of the boy.

The boy was playing outside with his seven-year-old sister Sunday afternoon, while their father watched them.

According to police, Adam's father had just stepped inside the house for a minute, when his daughter rushed in to say she could no longer see her younger brother.

Adam's mother, who was not there at the time of the disappearance, was treated for shock on Sunday but has since been released from hospital.

Adam is two feet tall and weighs 25 pounds. He was wearing a black and purple tuque and a black jacket and jeans.