After an explosion which rocked St. Helier on Saturday, emergency crews are yet to find any survivors.
The cause of the blast remains unknown as the fire service confirmed that they had gone to check the flats at about 20:30 GMT on Friday after the smell of gas was reported.
It is understood there were nine known residents in the block before the blast on Saturday morning.
Five bodies have been confirmed dead
It is estimated there could be up to a dozen, as details on visitors remain unknown
Specialist teams and a search dog have been carrying out searches at the scene.
Chief of Jersey Police, Robin Smith described how there had been a “meticulous and painstaking search of the debris following the explosion, to start carefully identifying bodies when and if we find them”.
He told the press conference: “That will take time. We are not going to be here for days we are likely to be here for weeks.”
Mr Smith said it was “difficult to be precise” on the total number of fatalities.
“The one area I can be precise on is we have three confirmed fatalities and it’s fair to say we expect to find more,” he said.
“Previously we have said in the region of a dozen but it’s difficult to make that assessment. That’s the number we hope we do not get to but that is the number we are working to.”
Smith said “around 40” people had been displaced because of the blast and the damage it had caused to nearby buildings.
When asked if the explosion could be a result of a gas leak, Smith said it was likely the case but also did not rule out criminal activities.
“It looks likely that is the case,” he said.
“But as you often hear the police service say, we keep all our options open.”
He added: “We will seek experts who are independent, as we would do with any investigation where there are particular specialisms – be reassured this will be an independent investigation.”
Jersey Chief Fire Officer, Paul Brown acknowledged something had gone “horribly wrong” and promised the full cooperation of the fire service.
The three-storey building that collapsed is owned by Andium Homes, a state-owned but independent company that rents out properties.
It said it was focusing on supporting residents at the estate.
On Monday, the flag of Jersey will fly at half mast on the island’s official buildings “as a sign of respect” for those affected by the explosion, the Government of Jersey said.
The flags will be lowered from 08:00 GMT until sunset on 23 December.
A one-minute silence will also be held at 11:00 GMT on Monday to give islanders a moment to “reflect on the incidents that have resulted in loss of life”, the government said.
