Two people were trapped after a large gas explosion caused devastation a guest house on a Blackpool Street.
Residents in nearby streets were evacuated after the major incident on Charles Street shortly before 6pm on Saturday.
A man and a woman trapped in the rubble had to freed by emergency services.
Residents were advised to avoid the area but have since been allowed to go home and roads in the area have reopened.
Witnesses reported seeing a hole blown in the front of a building and debris lying in the street.
Emergency services gave conflicting accounts of the number of people injured in the blast.
Police initially said six were hurt but said on Sunday a woman with 'significant injuries' and a man with 'minor injuries' had been taken to hospital. It is thought others were treated at the scene.
The North West Ambulance Service said it had taken two men to hospital following the blast, one with 'major trauma' injuries' and the other had minor injuries.
Force incident manager, Insp Kevin Otter, of Lancashire Police, said it was 'very lucky' nobody had been killed in the blast.
He said: "There were no fatalities. A female was trapped at one point and a male too.
"The female was released reasonably quickly. The male took a little bit longer but he was talking to us throughout."
Investigations are underway into the source of the gas explosion, thought to have been inside the property.
In a statement posted online on Saturday night, Blackpool Police said: "A safety cordon has been put in place and nearby residents on Charles Street and Milbourne Street have been evacuated.
"Road closures have been put in place on nearby Cookson Street and Grosvenor Street and people are being advised to avoid the area."
The force said anyone displaced by the evacuation order could go to either the Salvation Army Citadel on Raikes Parade or St John's Church, on Church Street.
Lancashire Fire and Rescue said in a statement shortly after the blast: "We've several fire engines and specialist appliances such as urban search and rescue team dealing with a suspected gas explosion in Blackpool.
"We were called just before 6pm to Charles Street. We're aware of people who have been injured, the nature of these injuries are not yet known."
A resident living nearby described seeing 'approximately six police vans, numerous police cars, two fire engines and ambulances and paramedic cars'.