Teenagers have been caught on camera on live tracks by a shocked onlooker, in footage Network Rail has branded "disturbing".

Sarah Parker couldn't believe what she was seeing when she spotted the trio on the tracks just minutes before her train arrived.

One of the girls is said to have even run across the tracks, which carry 750 volts of electricity.

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She said: "I wish I caught them more on camera, as the two girls went down onto the track and looked to be pushing each other and one ran straight across.

"Literally three minutes later my train was there. So lucky not to be hit!

"They were loud and it was a huge joke to them.

"I’ve reported it to Southeastern and British Transport Police."

Network Rail has warned train users not to trespass because of the severe risks those who do it can face.

A spokesman said: “These pictures are disturbing, particularly as a person was killed crossing the tracks at Broadstairs station in recent memory.

“Crossing a live railway means stepping over two deadly live rails, carrying 750volts of electricity, and running the risk of being hit by a train.

“Young people often think they won’t be hurt, but sadly our staff know only too well what can happen when they run terrible risks like this.

“There is no reason to trespass, so please don’t.”