There was standing room only again on the Wessex morning train

Commuters, including school children, said they were told they could not get on the train because it was full.

The furious passengers said they were left waiting at St Austell for about an hour and a half for the next service.

Wessex Trains said it is prepared to discuss the problem, but there is nothing it can do.

It does get busier when the schools go back Andrew Griffiths, Wessex Trains

Henry Robinson from Truro School did not get to lessons until 1040 BST and called it a "ridiculous situation".

He told BBC News: "There was anger and general shock and it was just not what you expected.

"I asked the people and was told 'because of the recent publicity we've been forced to follow protocol and only have so many people on the train'.

"The question you've got to ask them is why haven't they been following protocol before?"

'Unacceptable' situation

Earlier this week the train operator was criticised by a Cornish head teacher because of "dangerous overcrowding".

Schoolchildren said they were being forced to stand on the two-carriage train and sit in luggage racks on the Wessex service.

Paul Smith, head teacher of Truro School, said pupils were regularly arriving late and studies could be affected.

Matthew Taylor, the Truro and St Austell MP, said it was "utterly unacceptable" and he intends to take matters further.

Andrew Griffiths, the business manager of Wessex Trains, said the company would address the situation in April, but it could do nothing until then.

He said: "We have essentially been taken somewhat unawares by the extra large numbers of people wanting to travel into Truro.

"It has always been a busy train and it does get busier when the schools go back."