A teenager caught with a hunting knife down his trousers on a train could face being locked up.
Another passenger spotted Liam Ellis, then 18, with the fearsome blade on a Merseyrail service to Liverpool.
He phoned police with his concerns and the train was stopped at Kirkdale railway station, with the doors remaining locked.
Officers boarded the train and searched Ellis, when they recovered the weapon, at around 6.05pm, on May 14 this year.
Following his arrest, the teen, of Manica Crescent, Fazakerley, claimed that the weapon was "for his own protection".
Ellis, now 19, admitted possessing an offensive weapon in a public place at Liverpool Magistrates' Court on July 29.
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Magistrates sent his case to Liverpool Crown Court for sentencing and given his age, ordered a pre-sentence report to assist the judge.
However, his defence lawyer, Brendan Carville, today explained Ellis had not cooperated with the Probation Service and no report was available.
Judge Anil Murray agreed to adjourn the case, so a report could be made, as the teenager's mum and dad looked on in the public gallery.
He asked whether Ellis intended to enter a basis of plea and if the teen would cite past incidents, which made him decide to carry a knife.
Mr Carville said he didn't think Ellis would enter a basis of plea, before adding that the court didn't currently have a photograph of the knife.
Sarah Griffin, prosecuting, said she would obtain a photo of the weapon or have it produced at court when Ellis is sentenced.
Judge Murray said Ellis would be sentenced on September 16.
He extended the teen's bail but added a condition that he must cooperate with the Probation Service in the preparation of the report.
The judge told Ellis to stand and said: "If your intention is to try and avoid the immediate prison sentence that the law says has to be passed, you're not going about it the right way.
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"I'm going to give you one more opportunity. It will be your last. If you don't cooperate you will be sentenced without a report. Is that clear?"
"Yes," the teen replied.
Judge Murray warned Ellis that failure to comply with his bail condition could result in his arrest and remand in custody.
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He added: "I make no promises as to what will happen in this case. The judge – who won't be me – will have to take into account all the factors in this case, including any report that may be ready."
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