Commuters are facing more rail chaos this week on one of the main lines between Birmingham and London after four freight wagons derailed just outside Moor Street station on Tuesday.

The line, which runs from Snow Hill to Marylebone, was closed to allow work to begin on removing the wagons from the track and will not reopen until Thursday morning.

Chiltern Railways will still operate an hourly service to London from Snow Hill, but London Midland passengers who travel on services operating from Stratford-upon-Avon, Warwick and Leamington into Moor Street and Snow Hill stations, via Shirley and Solihull, will be most seriously affected.

A replacement bus service will be provided for travellers heading into Birmingham, as no trains will operate beyond Acocks Green and Spring Road stations until Thursday.

The derailment happened at Gibb Street, in Deritend, shortly after 6am when two freight wagons came off the tracks and one ploughed into a bridge wall, showering bricks onto a silver Citroen hire car parked 30ft below.

Network Rail and freight operator EWS have both launched investigations into what caused the 1.46am service from Aldwarke, in Rotherham, Yorkshire - which was taking scrap metal to Handsworth - to be derailed.

An EWS spokesman said the derailment happened at low speed as the train neared Moor Street station. The train driver was unharmed.

He added: "There were no injuries and a full investigation is going on at the site involving representatives from Network Rail and EWS."

Watch Commander Paul Hamilton, of Highgate fire station, said: "Fortunately, the wagon did not fall over the side of the bridge, otherwise the consequences could’ve been much more serious.

"However when it crashed into the side of the bridge, it dislodged around 10m of the wall.  The first thing we did was to check there was no-one in the car. Thankfully there wasn’t, as there would’ve been very little chance they would have survived.

"It’s lucky that nobody was injured in the incident and it happened at such an early time in the morning when there was nobody around."

The car was parked beside the Custard Factory office and retail complex.

Bennie Gray, the Custard Factory's owner, expressed amazement at the fact that no-one had been hurt.

"It was a miracle that somebody didn't get killed," Mr Gray said. "Just as the collapse happened, somebody was on their way to put something in the rubbish bins that we keep under the arches.

"That man could be dead."

* Passengers should check their travel plans with the train relevant train company, call National Rail Enquiries on 08457 48 49 50 or log on to www.nationalrail.co.uk.