This article was reproduced with the kind permission
of the British Broadcasting Corporation
13 November 2007, 19:59 GMT
Arthur McElhill, his partner Lorraine McGovern and their five children lived in the end-terraced property at Lammy Crescent in Omagh.
Deputy chief fire officer Louis Jones said the bodies were discovered in upstairs bedrooms.
"There are two further persons unaccounted for at this stage and our investigations are ongoing," he said.
He said the search had been scaled down until Wednesday morning on the advice of the police.
"In my 30 years of service, it has to be the largest loss of life in any house fire I have attended," he added.
None of the remains have been removed from the scene.
The cause of the blaze is yet to be ascertained.
The eldest of the five children, Caroline, 13, attended the nearby Sacred Heart College.
The other four were Sean, 7, Bellina, 4, Clodagh ,19 months and James, who was nine months old.
Sean and Bellina were pupils at St Conor's Primary School, which was closed following the tragedy.
The fire service arrived at the property at about 0500 GMT on Tuesday.
Earlier, neighbours had put ladders up to first floor bedrooms, but were beaten back by the flames.
Firefighters with breathing apparatus were also beaten back by the flames.
It is understood the property was already well-alight when firefighters arrived.
The fire was so intense that the roof collapsed.
Chief Superintendent Norman Baxter said police were investigating the cause of the blaze.
"It is very early in the investigation and we will be looking at a range of issues, including the period leading up to the fire," he said.
Parish priest Monsignor Joseph Donnelly said there was "disbelief and shock" in the community.
"It's hard to come to terms with the tragedy, that a family that was alive and well this time yesterday is gone," he said.
Local councillor Paddy McGowan - a former firefighter - said it was "one of the worst tragedies" he had ever seen.
Mr McGowan said the family had lived there for about four years.
Red Cross emergency support volunteers have been at the scene, comforting neighbours and traumatised firefighters.
Members of the Northern Ireland Assembly and first and deputy first ministers Ian Paisley and Martin McGuinness have expressed sympathy with the people of Omagh.
The Irish prime minister, Bertie Ahern, said the deaths were "truly heart-breaking".
"My thoughts and prayers and those of my colleagues are with relatives and friends at this sad time," he added.