Police have named five people who are missing after the explosion that destroyed a building in Leicester on Sunday night.

They said on Tuesday that human remains had been recovered from the wreckage but given the devastation caused by the blast and subsequent fire it could take some time before the victims were formally identified.

The missing include three members of the same family, Mary Ragoobeer, 46, and her two sons, Shane, 18, and Sean, 17, who lived in the flat above the Polish supermarket in the building flattened by the explosion.

Shane’s girlfriend, Leah Beth Reek, 18, and 22-year-old Viktorija Ljevleva, who was working in the supermarket at the time of the explosion, are also missing.

The rescue operation continued on Tuesday, as did efforts to establish what caused the blast.

Leicestershire police said the relatives of all five missing people had been informed and were being supported by specially trained officers.

One of the five people taken to hospital on Sunday night after the incident remained in hospital with life-threatening injuries, they added.

Ragoobeer’s youngest son, Scotty, 15, was taken to hospital but his injuries were not serious, according to his uncle Krishna Rungen. Scotty’s father, Jose Ragoobeer, was at work at the time of the blast.

“Scotty said the family were watching television when the next thing he knew, everything went black and there were bricks flying around him,” said Rungen.

The 69-year-old, who said he was supposed to be going on holiday with his sister and her family in April, has been a regular visitor to the site of the explosion since Sunday, trying to find out information about his missing relatives. He said he was devastated by the thought that his sister and two of her sons could be among the dead.

The owner of Zabka, the Polish supermarket, which opened in December, told ITV he had gone into the storeroom to get drinks for himself and Ljevleva when he heard a loud bang. He managed to escape but had not seen Ljevleva, who had only recently started work there, since.

Police said the rescue operation was being complicated by expected heavy snowfall and as a result they expected Hinckley Road to remain closed for all or most of Tuesday. At a community meeting on Monday night, Matt Cane, the group manager for Leicestershire fire and rescue service, said the search was “dynamic and challenging”.