A man who posed as an MI5 officer and was seen carrying out an apparent drugs detection operation at Dagenham Heathway Station with his pet dog, has received a suspended sentence.

Jason Peter Marshall, 23, was sentenced at Blackfriars Crown Court on August 1 after pleading guilty to two counts of impersonating a police officer, one count of handling stolen goods and one count of possession of a false ID card with improper intention.

The court heard how Marshall was seen by station staff apparently conducting a drugs detection operation with his pet Scottish terrier at Dagenham Heathway on April 6. When challenged he said he was working for MI5 but was on secondment to British Transport Police (BTP).

He produced a fake ID card and gained access to an office where he stole a London Underground radio.

Two days later, Marshall, of Monega Road, Forest Gate boarded a District line train at Elm Park station and began checking people’s tickets with an Oyster Card reader stolen from Barking station. A revenue inspector became suspicious and Marshall produced the fake MI5 card and declared he was helping BTP check tickets.

The inspector was not convinced and took the card reader, ID and radio from Marshall and got off the train at Upney to summon police. BTP officers arrived and Marshall was arrested.

BTP Detective Constable Graham Hempstead said: “When he was arrested he repeated to police that he was working for MI5 and that he couldn’t reveal any more details due to the nature of his work. He was, of course, lying and pleaded guilty in court to impersonating a police officer on both occasions.

“Although I have never seen a terrier being used as a drugs dog before, Marshall was quite convincing in his actions which could have had serious consequences. He was committing a serious offence by pretending to be a police officer and has rightly been punished.”