Up to 18 neighbours helped pull a woman and two children from the rubble of an exploded house, one of the rescuers has said.
Neighbouring properties were also badly damaged in the blast on Church Road in Seven Sisters, Neath Port Talbot, at about 14:05 BST on Wednesday.
Both children were flown to Southmead Hospital, Bristol, and the woman was taken to Morriston Hospital, Swansea.
Police said they suffered serious injuries.
Retired firefighter Jeff Davies, who was one of the first on the scene, said he scrambled to the house after hearing a bang and a woman screaming.
‘Your natural instinct is to help’
He told BBC Radio Wales Breakfast he and five neighbours rescued the mother from debris in the back of the house while about six pulled the children free.
He said: “It was unbelievable the scene, shocking.
“Normally the wise thing would be to stand back and watch and let others come but obviously there’s always a delay until the services come and when you hear people and know there’s people in the building your natural instinct is to help.
“Thankfully there must have been about a dozen people at the front of the property and there must have been half a dozen along with myself helping out the back – It was a great community team effort.
“Other volunteers, residents had pulled the children out from the front of the house.”
He said he and his neighbours moved the woman using joists from the collapsed roof of the house.
“She was immense. Such a brave young lady,” he said.
“She was injured herself and very concerned for her children.”
Fourteen nearby properties were evacuated following the incident.
Speaking on Wednesday night, a spokeswoman for South Wales Police said all three had suffered serious injuries and the cause of the explosion was being investigated.
“The road will remain closed overnight and diversions are being put in place,” she said.
Community councillor Gary James told Radio Wales Breakfast: “We’re a close-knit community and I know for a fact that the neighbours rushed to the scene…
“It’s a major shock to the community and our thoughts are with the family who were living there.”
She said Neath Port Talbot had opened a rest centre for residents.
Kirsten Alison Williams, who was visiting family nearby, said the explosion made their conservatory shake.
“What shook me the most was a small, baby teddy bear was there laying on top of the car roof,” she said.
Utility company Wales and West Utilities said it sent emergency engineers to assist.
Neath Port Talbot council leader Rob Jones thanked the emergency services for their swift response and said the council “stands ready to offer whatever support is required”.
“My thoughts and those of my council colleagues are with those who were injured in the explosion,” he said.
“I know that Seven Sisters is a close-knit community, and that many will be feeling a mixture of shock and sadness at this time.”
Reporter Kathy Peart was at scene hours after the explosion
“I can see a lot of rubble and things from the house strewn across the street.
“There’s essentially a gap where the house was.
“I’ve spoken to a couple of neighbours here – one told me he was at home when he felt an explosion.
“He said it shook the house and when he looked out he could see plumes of smoke and the roof had been shot 40ft into the air.
“There’s been damage to neighbouring houses, there’s been damage to vehicles.
“The house itself is irreparable.”