The use of single-carriage trains on a crowded coastal service has been branded 'unacceptable' by MP Sir Norman Lamb.
The North Norfolk Lib Dem has demanded an explanation from rail firm Greater Anglia, following reports single-coach trains were being used on the Norwich-Sheringham 'Bittern Line' at a higher rate than before.
But a Greater Anglia spokesman said just five of the 26 diesel trains it used on rural lines were single carriage, and a mix of one, two and three carriage trains operated between Norwich and Sheringham.
On July 22, this newspaper reported on passengers' frustrations at overcrowding on Bittern Line trains, with one July 19 service reportedly having "hundreds" of people aboard one carriage.
Sir Norman said in a letter to Greater Anglia: "The reports of overcrowded service on the Norwich to North Walsham line are incredibly frustrating.
"I'm sure this sentiment is shared by the commuters on the line who are having to endure standing room only conditions too frequently. In the current hot weather, having to stand in an overcrowded train can be incredibly unpleasant."
Greater Anglia apologised for passengers' frustrations, and said its fleet of new 'bi-mode' trains were gradually being introduced around the network.
A spokesman said: "We are very sorry for any inconvenience that customers have experienced recently on the Norwich-Sheringham line.
"Our new trains will be longer with more seats. People will have seen them on test around Norfolk. We're working hard to bring them in as soon as possible - but first they have to pass all performance and safety tests.
"As soon as we won our long franchise, we ordered new trains as passenger numbers are growing and we want to give our customers the best possible travelling experience."
The Bittern Line connects Norwich to the north Norfolk coast via Hoveton and Wroxham, North Walsham and Cromer before terminating at Sheringham.
Passenger numbers on the line have risen from around 200,000 to more than 600,000 in the past 20 years.
The line has recently seen a £1 million replacement of the platform at Sheringham station. Greater Anglia has also faced calls to scrap new parking meters at stations including North Walsham and Wroxham and Hoveton.
-What has been your experience of travelling on the Bittern Line? Email your comments to stuart.anderson@archant.co.uk
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