Rescuers searching for the last person known to be inside the Glasgow plastics factory when it exploded said last night they believed they were "very, very close" to finding him alive.
As police named the eighth victim to be killed in the blast as Kenneth Ronald Murray, 45, from Paisley, Strathclyde, the Strathclyde Fire Brigade Firemaster, Brian Sweeney, who has been co-ordinating the rescue operation, said he was still optimistic of finding the missing factory worker.
"If I thought there was no chance of anyone still being alive in there I would not be risking my firefighters lives in a futile rescue attempt," he said.
The man's family have been waiting in a nearby community centre desperately hoping for a breakthrough in the search.
Eight people died and more than 40 others were injured, some seriously, when the Stockline Plastics factory the Maryhill area of the city was destroyed by an explosion at noon on Tuesday.
More than 200 rescuers have been involved in a round-the-clock operation to locate survivors and managed to pull seven people alive from the wreckage on Tuesday.
Despite time since the blast, Mr Sweeney said evidence of earthquake victims in other countries had shown that people could survive for days buried in the rubble of collapsed buildings.
Thermal imaging cameras, sensitive sound devices, information from fellow survivors and tracing the sound of the signal of a man's mobile phone have led rescuers to a small part of the site at the back of the collapsed building. "That area represents our best hope, it's not our only hope but it represents our best hope," said Mr Sweeney. "We are getting very, very close and I've conveyed that to the family.
"We have taken an overview and thermal imaging overhead shots of the building with a helicopter. We hope it will identify any hotspots that remain in the building. We are acting now on more specific information."
He said the rescue effort was a "deliberate, painstaking and dangerous task", hampered by steel girders which could result in the firefighters making only six inches of progress in one hour.
The family of the unidentified missing man have been waiting only yards from the scene. "The family are very, very, very distressed," said Mr Sweeny, the senior Strathclyde fireman. "They asked me to pass on their regards to the firefighters who are risking their lives to save this man. Basically they asked me to get him out."
At the blast site, firefighters suspended in cages from two 100ft cranes are co-ordinating the rescue effort from above. During the day, some of the families of those killed visited the site of the explosion.
Relatives of office worker Annette Doyle, 34, laid flowers at the site perimeter as more than 100 rescuers continued digging just a few yards away.
Just before 5.30pm, Annette McAuley, who lost her husband, Thomas, in the blast, also laid a bouquet at the scene.
A short time later, the family of Tracey McErlane paid their respects at the site. Ms McErlane, 27, of Possilpark, Glasgow, was a receptionist at the plastics factory. It was reported yesterday that she had only recently returned to work following maternity leave to care for her son, Ryan. Her devastated mother laid a bouquet.
At the corner of the street just a few hundred yards from the factory site, a steady stream of locals came to lay floral tributes to those killed.
Messages of sympathy came from as far away as Sydney, Australia. Some of the messages were from local shops and businesses and many from people in the local community shocked and grief stricken at the tragedy that took place on their doorstep.
Among the messages was one which read: "To Dad, love u always and forever. I will never forget you. Love Sarah and Caitlin."
Another message read: "To the best work colleagues a guy could ever have."
One message for victim Annette Doyle, who was a keen karaoke fan, read: "Crosslands' very own Pop Idol will be very sadly missed by everyone, God bless." Another tribute to Ms Doyle, written in a card placed beside a single red rose, read: "Here is your rose. I will miss you so much. I have a love for you that will never die. Ya maddy. Goodbye. Love Steve."
Although the authorities claim to have found no evidence to suggest the disaster was anything other than an accident, Chief Superintendent David Christie of Strathclyde Police said the site was being treated as a scene of crime while inquiries are being carried out.
"We won't rule anything out yet, we'll treat it as a scene of crime until it's determined not to be," he said.
"But at this stage there's no indication there has been a crime. We don't know what the cause of this accident is but we have to obviously ensure there's a thorough investigation to determine the cause."