Forty people had to be evacuated when burglars used acetylene cylinders to blast off a shop’s door and cash machine in part of Cardiff.
South Wales Police said the explosion at about 04:00 GMT at the Co-op in Llanrumney caused “significant damage”.
About 40 people living in the flats above the shop had to take refuge at a nearby branch of Greggs.
Councillor Keith Jones said the offenders showed a “complete disregard for human life”.
Two South Wales Fire crews were also at the scene in Countisbury Avenue but there have been no reported injuries.
Mr Jones said he and his fellow ward councillors had previously successfully campaigned to install two CCTV cameras at either end of the parade of shops.
He urged police to “urgently review” the footage of what happened in the early hours and see if anyone could be identified.
Llanrumney councillor Lee Bridgeman said when the 11 families were evacuated from their flats uthe leisure centre and hotels were put on standby to look after them.
A spokesman for Cardiff Council confirmed the Resilience Unit at the council was called by the emergency services at 04:00 GMT.
They said: “Following a failed attempt to remove an ATM machine from the Co-op store on Countisbury Avenue, a fire was started at the building, which caused an immediate danger to those living in flats above the shops.
“The council was responsible for the evacuation and shelter of 40 people during this incident, who were firstly moved to a safe distance, and then moved on to a bus until more suitable accommodation could be found.
“All protocols and procedures were followed and the incident ended at 6.30am. The residents have now been moved back into their properties and the council is continuing to support the emergency services while investigations continue.”
Philip Lancefield, who owns a greengrocers in the same parade of shops, said there had been a few break-ins and a ram raid on the Co-op two years ago but nothing as significant as Friday’s .
Mr Lancefield said: “I’m not particularly worried about my business being targeted but what’s happened is affecting trade here today.”
Kieran Davenport, who lives opposite the Co-op, said: “I didn’t hear it because I was asleep but others in the house heard an explosion and a car screeching away. It happened at about four in the morning.
“It all happened really quickly. It’s been targeted a few times in the past but I don’t think they’ve ever got away with much before.”