A woman was taken to hospital suffering from smoke inhalation after a "discarded cigarette" started a flat fire in Fleetwood, say fire services.
The 21-year-old was found outside her home on Windsor Place at around 6.30pm on Sunday, January 7 after an alarm sounded.
Firefighters from Fleetwood attended the scene to find a "well established" fire and searched the property over fears that other people were trapped.
A fire service spokesman said: "We believe a discarded cigarette set fire to clothing.
"Firefighters wearing breathing apparatus searched the building and found that nobody was trapped although several people had failed to respond to the alarm.
"Around four or five other people were led to safety.
"We used a hose reel to extinguish the fire and thankfully damage was confined to a first floor room.
"A young lady was treated for smoke inhalation and taken to Blackpool Victoria for a precautionary check-up.
"Please always respond to fire alarms and stay out of the property until fire fighters say it is safe to return."
Nobody is believed to have been seriously injured in the incident.