Police in B.C.'s Fraser Valley have executed a search warrant at the home where a toddler was found dead in the hopes of finding out exactly how he perished.

Dillon Walker, 18-months-old, died after a blaze swept through the Silver Creek home he shared with his mother and her boyfriend around 1:30 a.m. Thursday.

A neighbour told CTV News the boy's parents were not at home at the time of the fire.

Cpl. Tammy Hollingsworth said officers conducted a primary sweep of the home Thursday night as part of a criminal code investigation. Officers were expected to be at the home Friday for further scene examination.

Investigators say the cause of the fire and the boy's death will remain unknown until an autopsy and forensic probe are complete.

"Our investigation is clearly focused on the cause of the fire and the cause of death of the child," said Hollingsworth. Police haven't said if the child's parents are facing any charges.

"The results of the completed scene examination will determine the next course of our investigation."

Neighbour Diana Warren said the children's parents returned home from a late night walk to find their home engulfed in flames.

"The mother started screaming. I didn't know it was her until she fell to the ground saying ‘that's my baby, my baby's in there,'" Warren said.

Dillon's older brother Quentin was away visiting a relative at the time of the fire.