Narrogin detectives are investigating a suspicious house fire in the early hours of Friday morning on Ensign Street. Emergency services were called to the residence in Narrogin at about 4am with fire fighters arriving to find the lounge room engulfed by flames. Crews worked to bring the fire under control and it was contained by 5am. The damage to the home was contained to the lounge room and the occupants of the home escaped without injury. A police spokeswoman said the cause of the fire was being treated as suspicious and local detectives were investigating. That investigation remains ongoing and police remained at the scene on Friday. A Department of Fire and Emergency Services spokeswoman confirmed they attended the home on Ensign Street. Two crews from Narrogin Volunteer Fire and Rescue Service helped put the blaze out.