A man was also seriously injured as a result of the incident in Sefton Terrace, off Piccadilly Road, yesterday afternoon.
It is not known at this stage what caused the explosion and partial house collapse but gas engineers were seen working at the site following the incident, alongside emergency services personnel.
Three fire engines, an air ambulance, two land ambulances, an advanced paramedic and an operational commander attended alongside police.
“We have conveyed two patients to hospital,” a spokesman for North West Ambulance Service said.
“A man has been airlifted to Royal Preston Hospital suffering major trauma. A female patient was taken to the Royal Blackburn for assessment.”
Residents were evacuated from 10 neighbouring houses and told to go to St Matthew’s Church on Albion Street.
A spokesman for Lancashire Fire and Rescue Service said at the time: “We have three fire engines and our urban search and rescue team at the scene.
“We’re working with the other emergency services, local authorities and utilities companies to make the scene safe and assess the structure of the property.
“Firefighters at the scene are using an aerial ladder platform to make the structure of the house safe by removing coping stones from gable end.”
A spokesman for gas emergency service Cadent said: “There is a multi-agency response to the incident in Sefton Terrace, Burnley, and our teams are assisting as Lancashire’s gas emergency service.
“We will make sure everything associated with gas is safe.
“It is too early to speculate on the cause. Our thoughts are with everyone impacted.”