A man and a woman had to be freed from rubble by firefighters after a gas explosion caused "significant" damage to a guest house.
The pair were trapped after the blast at about 5.55pm on Saturday in Charles Street, in Blackpool, Lancashire.
Paramedics, firefighters and police went to the scene and nearby residents in the road and neighbouring Milbourne Street were evacuated.
A spokesman for Lancashire Police said: "A number of people have been treated by paramedics at the scene and two people who were rescued have been taken to hospital."
Describing the rescue, a spokesman for Lancashire Fire and Rescue Service said: "When fire crews arrived, they found there had been a significant explosion. After speaking to local residents we knew there were two people inside.
"One of them was on the phone to our control room saying they were inside, and we could see another casualty.
"Firefighters had to sift through the debris, obviously being careful - there was still most likely a gas leak and the property was insecure. We had our urban search and rescue team on the scene.
"They were physically trapped. One had to be lifted down from the first floor on the ladder on a longboard.
"We don't believe anyone else has been injured.
"It's a row of terraced properties and this one house or block of flats, the front of the house is missing and around the back, part of the property has caved in.
"This has just caused significant damage to one terraced property."
Gas engineers had been called and were investigating the cause of the explosion, he added.