Three people were rushed to hospital, with one person still missing, after a suspected gas explosion in Swansea, South Wales Police said.
Emergency services are continuing work to try and locate the unaccounted person.
Two properties have been extensively damaged, with neighbouring houses also affected. Engineers are working to establish the cause of the blast.
“Our thoughts are with everyone who have been affected by this morning’s incident and we would like to thank the community for their support whilst this incident is ongoing,” South Wales Police said.
One of the people involved has been named locally as Brian Davies. A teenage boy and his mother were rescued from the rubble, according to neighbours who live on the street.
A rest centre has been set up with emergency services supporting residents affected.
Councillor Ceri Evans, who represents Morriston on Swansea Council, said around 100 people had been evacuated following the blast.
South Wales Police and Mid and West Wales Fire Brigade have been at the major incident in Morriston and are appealing for people to avoid the area.
The blast was felt by houses miles away from the explosion.
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The blast was felt in houses miles away from the explosion
Ioan Humphreys, who lives eight miles away in Rhos, Pontardawe, was on a Microsoft Teams meeting when he heard the bang.
“The house next door to me is having lots of building work done, so initially I thought it was a massive skip being delivered and dropped on their drive – it felt that close,” the 48-year-old Swansea University research officer said.
Another local resident, Sian Murray, told Sky News that she had never heard anything like it in her life.
The junction of Clydach Road and Field Close in Morriston, Swansea
“It was unbelievable. It was quite shocking actually. I walk past there practically everyday with the dog, so it is really scary,” she said.
Ms Murray described the community in Morriston as “very close knit” where everybody knows everyone.
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Suspected explosion was ‘like an earthquake’
She added: “[It is] shocking that it could happen. It makes you realise how dangerous gas is. I’m just shocked.
“I didn’t know what it was. It was like an earthquake. It was just really loud.”
Earlier, police said they were called just after 11.20am on Monday to reports of an explosion at a property on the junction of Clydach Road and Field Close.
Mid and West Wales Fire and Rescue Service said crews from Morriston, Swansea West, Neath, Gorseinon and Port Talbot were called following “several reports” of a gas explosion.
In a statement, Wales & West Utilities, which maintains the gas network across Wales and the southwest of England, said: “We were called to reports of an explosion at a property in the Clydach Road area of Swansea and immediately sent a team of engineers.
“On arrival, we found that there had been severe structural damage to the property and the emergency services were in control of the scene. We are now working with them to make the area safe – as we do on all incidents of this nature.
“We do not yet know the cause of the explosion and our engineers will continue to support the emergency services as they carry out their work.”
The Welsh Ambulance Service also confirmed it attended the scene after receiving reports of an explosion.
