The group covered trains in paint during night time "tagging sessions"
Four graffiti vandals have been jailed after admitting causing an estimated £50,000 of damage to trains and chaos to services in the South East.
Tom Collister, 22 of West Wickham, London, and Darren Austin, 21, of Beckenham, London, received 30 months and 18 months in prison respectively.
William Setzdemspey, 19, of Hillmead, Uckfield, Sussex, was given a 15-month sentence at Southwark Crown Court.
Joshua Phiel, 19, of Tunbridge Wells, Kent, was sentenced to 12 months.
They had earlier pleaded guilty to conspiracy to commit criminal damage.
The court was told the group caused chaos to the rail network for two years because carriages were covered in so much paint they had to be withdrawn from service to be repaired.
They even carried on their planned night time "tagging sessions" after one of them suffered a shock from a 750 volt live rail, British Transport Police (BTP) said.
Detectives linked the two so-called crews, Just Kant Stop and Forever Doing Crime, to Austin, Collister, Phiel and Setzdemspey, after a lengthy investigation.
Following their arrest in Hertfordshire April 2007, photographs and paint cans were seized from their homes.
Vehicles belonging to Collister and Setzdempsey containing spray cans and masks were also confiscated by officers.
BTP said the materials helped identify them as being responsible for attacks in East Grinstead and Horsham in West Sussex, Hastings in East Sussex, Epsom, Redhill and Woking in Surrey, Tunbridge Wells and Ramsgate in Kent and Bletchley in Milton Keynes.
Det Sgt Pete Thrush said: "In 2004 Austin was arrested for trespassing on the railway in an incident where he received an electric shock from the 750 volt live rail.
One of the tags which was painted by Collister
"Yet he continued to trespass to spray graffiti on trains and sidings."
He added: "Numerous bits of graffiti paraphernalia were seized during various house searches.
"Many had tags linking back to each of them on everything from railway timetables to shoe boxes, with even a pair of slippers being seized with their tags on it."
He said phone text messages discovered by officers showed the planned activities.
Det Sgt Thrush said: "These people are persistent dedicated vandals. The court has recognised the seriousness of the offences, the risk these young men take with their lives and the cost to the train companies and public.
"I would rather see people go to court than go to the morgue."