A Lithuanian tourist caused a seven-hour disruption to passengers at Ipswich railway station when he climbed onto the roof after trying to dodge a fare.
Mantas Badauskas, 25, sparked the £1 million stand-off last Friday that saw massive disruption for 40,000 commuters and festival-goers to nearby Latitude.
According to the Ipswich Star, police, firefighters and paramedics were called to the scene and the financial cost to Greater Anglia for not being able to run its services is said to be £1 million.
EADT24 reports that Badauskas was returning to Lithuania after a week's holiday in England and tried to use an Oyster Card at Ipswich station, thinking the town was part of Greater London.
But when he was told he must pay for a ticket to Stansted Airport, he clambered over the roof in an attempt to bypass the ticket barriers.
Badauskas was standing close to 25,000 volt power cables, which had to be switched off, and police feared the glass and asbestos roof was not strong enough to support his weight.
A court heard how around 750 passengers were trapped in three trains without power or air conditioning on the scorching hot day.
According to the Daily Mail, Tess Mann, prosecuting, said: "He thought he could get the train to Stansted by going on the canopy.
"When he realised he couldn't, the police had already seen him.
"He was frightened to go back down because he was scared of being arrested."
The 25-year-old will be sentenced at Ipswich Crown Court as magistrates felt their sentencing powers were insufficient.
Badauskas could be jailed for up to two years.
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