New high-tech trains on the troubled Southend to Fenchurch Street line have been withdrawn from service four weeks after they were launched, it has emerged.

The £300million fleet of air-conditioned trains was meant to signal a new beginning for LTS - but only four trains ever ran on the line because the company hit snags on the production line.

Now the flagship Electrostar 357 trains have been completely removed from service after problems with the power supply and on-board computer glitches.

Commuters will be forced to revert once again to the 40-year-old slam-door stock for the 50-minute journey to Fenchurch Street.

In a flyer handed out to frustrated rail passengers, Andrew Chivers, director of LTS, said: "We have had technical teething problems and need to find a solution to an engineering problem.

"This is receiving urgent attention by our suppliers.

"I will not accept these trains into service until I'm completely satisfied that our customers are provided with a reliable and comfortable journey.

"We have promised this in the past and I feel the public deserve nothing less - albeit later than we would have wished. Please be assured the problems are receiving my personal attention."

The surprise withdrawal signals bad news for commuters on the route - once dubbed the "misery line" - who were looking forward to new air-conditioned units as summer approaches.

The shock decision comes despite a massive £300million investment programme, plus £40million funding for station improvements and a surprise £20.5 million boost revealed by LTS's parent company, Prism, on Friday.

More bad news is also on the way after LTS admitted the old trains are becoming increasingly difficult to maintain.

Mr Chivers said: "Our fitters have an increasingly difficult task in keeping these trains in service, which is why we have the current short trains and cancellations.

"Although every effort will be made to keep disruptions to a minimum, significant improvements in the service are going to be hard to come by until more of the new trains are in operation.

"But we will be maximising our efforts to get the best service possible from the resources available to us."

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