Tens of thousands of commuters have been prevented from returning to work by the overrunning of engineering work on one of the UK's busiest rail lines.
The West Coast main line remains shut today after engineering work scheduled to finish before the new year overran again.
Virgin Trains is advising customers not to travel on sections of the line, with Rugby and London's Liverpool Street stations completely shut.
According to its managing director Chris Gibb, the disruption is a "major inconvenience".
Network Rail, which managers Britain's railways, agrees with Virgin that the unfinished engineering work is "unacceptable".
But it insists that the project, which has seen stations shut between Coventry, Birmingham and Northampton, is "extremely complex".
"An investigation into the causes of this unacceptable engineering overrun has been launched and Network Rail is deeply sorry for the further disruption this news will cause to passengers who use services on this route," a statement said.
Virgin's Mr Gibb explained the firm was "deeply concerned" about the delivery of the engineering work project.
"Virgin Trains' staff have coped magnificently with unexpected disruption on New Year's Eve and New Year's Day and our customers have shown great patience. I'm sure their patience, like ours, has now run out," he continued.
Train operator One Railway, which has also seen its services hit by the engineering work, said: "We and Network Rail are doing everything possible to ensure that services return to normal as soon as possible, but at the moment it is not possible to be precise about the effect on individual services.
"We do advise not to travel into London if your journey is not important. We do apologise for the inconvenience caused."
The major disruption comes as train fare rises of up to 11 per cent an average of 4.8 per cent come into effect.
Passengers to and from London are being urged to use alternative routes for their rail journeys:
Coventry - CrossCountry/Chiltern Railways via Leamington to Marylebone Birmingham - Chiltern Railways to Marylebone Nuneaton CrossCountry/East Midlands Trains via Leicester to St Pancras Rugby - Drive to Kettering then East Midlands Trains to St Pancras North-west England - Trans Pennine Express/East Midlands Trains via Sheffield to St Pancras North Wales - Virgin Trains/CrossCountry/Chiltern Railways via Birmingham to Marylebone Scotland National Express East Coast to Kings Cross