A woman was run over by a 60mph express train - and walked away without a scratch.

Passengers were stunned when the 46-year-old from Worthing leapt onto the track at Lancing station moments before the 10.04am to Brighton approached.

The driver - who was travelling at 70mph - sounded his horn and braked to give the woman time to move but she positioned herself between the rail lines and waited to be crushed.

When the two-carriage train rumbled over without touching her, the dazed woman crawled to the side of the track and climbed onto the platform.

Station staff then tried to calm her and stop her jumping back onto the lines before the police arrived to restrain her.

British Transport Police said last night the woman's chance of survival had been less than one per cent.

An witness who was waiting for her boyfriend to arrive at the station said: "A woman was standing on the bridge and jumped.

"She fell face down and rolled herself around so she was staring at the undercarriage but the train went over her.

"There was only me and two other people on my side of the platform and one other person on the other side and we all looked on in shock.

"She then panicked because she thought she should have been dead.

"Then she crawled across the track and climbed up to the platform but she wasn't screaming or crying.

"When the police grabbed her she was fitting and shaking and they put her in an ambulance for a check before taking her away in a police car.

"I'm surprised she didn't brake any bones but even if she did she was probably in too much shock to notice."

The South West Trains service from Reading to Brighton passed through Lancing at around 11.45am yesterday without stopping.

Police have taken the woman into custody under the Mental Health Act.

Inspector Gary Ancell, of the British Transport Police, said: "She did not get injured and this can be done because some trains are higher above the tracks than others.

"It is very, very rare that someone would survive falling in front of a train.

"She was very lucky because she must have laid completely flat."

South West Trains did not need to delay it services as a result of the morning's events.

Spokesman Simone Spinks said: "The driver reported to be fine and was able to take the train to Brighton."