Technicians had been asked to repair the set of points at the heart of the Cumbria rail crash a week before the accident, according to industry sources.
Fears were raised about the state of the points by the crew of a " tamping" machine, which beds the track down, the sources said.
Network Rail, which is responsible for the tracks, said last night it had "no record" of the events, but added that it could not deny the authenticity of the account.
It is understood that the machine's operators and the maintenance personnel summoned to the site were all employed by a private company rather than by Network Rail. It is not clear whether the technicians carried out the inspection of the points, which are only used in emergencies and when engineering equipment needs to switch from one track to the other. According to an official log the points were last used on 15 February.
Bob Crow, the leader of the RMT, the industry's biggest union, said: " If this turns out to be true, it shows just how big a muddle has been caused by privatisation. The left hand doesn't know what the right hand is doing. There's only one way to run the railways and that is like a ship. There should be one captain and that captain should be Network Rail."
Initial findings of the investigation into the 90mph derailment will be released today, although a full report will not be completed for months. Yesterday, safety experts completed their inspection of 700 points throughout the network and found "nothing out of the ordinary". It is thought that a catastrophic failure of a set of points was at the heart of the disaster in which a Virgin Pendolino train on its way from London to Glasgow careered off the tracks on Friday night, killing an 84-year-old woman and injuring dozens of other passengers - 11 seriously.
Thomas Edwards of the Department for Transport's Rail Accident Investigation Branch, said the investigation was focusing on four main areas - the points; the track between the points and the train; the vehicles and other factors such as signal boxes and maintenance depots.
Speaking in the village of Grayrigg, near the site of the accident, he said it was too early to say whether poor maintenance may have been a factor in the accident. He said the investigators would find out whether that part of the track had been patrolled, inspected and maintained to the required standard. Mr Edwards said the full investigation would take months. " There is a wealth of detail to go through, we have a lot of witnesses we are keen to talk to," he said.
Weather conditions yesterday near the site hampered attempts to move the train. Heavy lifting equipment will be needed, but the only access to the area is via narrow rural roads. A senior source close to the industry said: "I believe the media has been very gentle with the industry over this. Here we have one of the most expensive and sophisticated trains in Britain lying on its side at the bottom of a muddy embankment near the most expensive piece of railway on the network which in turn is the responsibility of the highest paid public servant in the country."
The state-backed Network Rail is spending £8.3bn maintaining and renewing the West Coast Main Line. John Armitt, Network Rail's chief executive, was paid £857,000 in 2005, according to the latest accounts.
Disruption to West Coast line
The derailment will cause disruption for at least a week. Virgin will run regular services between London Euston and Lancaster but passengers will face a 100-mile coach journey from there to Lockerbie before picking up a second train to Glasgow. The journey is expected to take up to 60 to 90 minutes longer.
The East Coast Main Line between King's Cross and Edinburgh will accept passengers with West Coast tickets. Twenty million people use the West Coast route every year and flights between London and Scotland are expected to see an increase in passengers.
'I am shocked and upset by what has happened' The driver: Iain Black, 46
Colleagues of the derailed train's driver heaped praise on him yesterday as he came to terms with how close to death he and many passengers had been. Iain Black, 46, who is lying horizontal in bed with his neck in a brace at the Royal Preston Hospital, is said to be "shocked and upset" by what had happened and has told one friend he has very little recollection of the last minute before the crash, in which he stayed at the controls while the train careered along stone ballast.
Mr Black's decision not to abandon his seat and seek refuge in one of the carriages led Virgin Group chairman Sir Richard Branson to describe him as "a hero" on Saturday. Colin Smith, an Aslef union representative who visited Mr Black yesterday, said: "He acted very bravely." Mr Black escaped with a broken bone in his neck and a broken collarbone.
Family suffers a second rail accident tragedy The victim: Margaret Masson, 84
The 84-year-old victim Margaret Masson was returning home to south Glasgow after visiting her daughter in Southport, when the derailment occurred.
Known as "Peggy", Mrs Masson was a keen cook who had run a catering business for many years. "She was still very active and was always out and about," said Mhairi MacDonald, who lived near Mrs Masson at Tarfside Gardens - a small block of flats in the city's Cardonald district, her home for many years. "She did her own thing and she always seemed to be on the go."
Mrs Masson's death was the second rail tragedy to strike her family in 10 years. Her great nephew Stephen Masson, died aged 10 in October 1996, after he was electrocuted when he touched a 10,000 volt overhead power cable with a metal pole while playing. He and his friends had climbed through a fence on to a railway track at Corkerhill station in Glasgow.
Mrs Masson, who leaves three sons and a daughter, died in the Royal Preston Hospital shortly after the crash. Her daughter Margaret Langley, 61, and son-in-law Richard, 63, remain in a "very serious" condition, according to hospital staff.