A safety probe is under way after two carriages on an empty passenger train came apart as they were moved in a shunting yard in Shoebury.

Experts were today (Friday) examining the coupling equipment on the slam-door train, built more than 30 years ago.

LTS Rail spokesman Les Powell admitted the consequences could have been serious if the train had been full of passengers. But he stressed the class 310 had an "excellent" safety record.

The Fenchurch Street line currently has 35 class 310 trains and 25 312s. As a precaution, LTS Rail has now locked all connecting doors between carriages.

Posters were also going up at the 25 stations on the route between London and Shoebury, apologising to passengers for any inconvenience.

Mr Powell said: "Passenger safety is always our top priority so the connecting doors will remain locked until we are completely satisfied that there is no possibility of a recurrence.

"In the meantime, passengers will not be able to walk through trains at busy times to find a seat and access to toilet facilities will be limited."

Mr Powell said engineers will be focusing their investigation on the coupling device linking the train together.

He added: "Based on their expert opinion, we will then decided whether it was an isolated incident and then we will be guided by the recommendations of the engineers.

"If it is something that is likely to affect other trains, then a full inspection will be carried out. This is an extremely rare occurrence - the first of its kind as far as we know."

LTS Rail is still on target to replace two thirds of its slam door trains by the end of this year. The company has ordered 44 new, state-of-the-art trains at a cost of more than £220 million.

There will still be some slam-door trains in operation until March 2002.

Converted for the new archive on 19 November 2001. Some images and formatting may have been lost in the conversion.