A man who masturbated in front of passengers on the London Underground has been jailed for 21 months.

Justin McCarthy would stare at women and attempt to gain their attention by tapping their legs with his feet before touching himself beneath his clothing, the police said.

The 37-year-old, of no fixed abode, appeared at Highbury and Islington Magistrates' Court on March 28 and pleaded guilty to multiple charges.

One man witnessed the offender masturbating on a Central Line train on August 8 last year.

His name has been changed to protect his identity.

Speaking after the sentencing, James, 38, from Ilford, said a mixture of women and children were on board at the time.

“[McCarthy] was slouched back with his legs spread and I noticed that he had one hand inside the waistband of his jeans and was masturbating,” he said.

“The man leaned over towards the woman and began whispering into her ear.

"She immediately stared straight ahead looking horrified, I made eye contact and stood up to give her my seat.

“I stood between the man and the woman to block his view of her.

"There were other women and children on the train and I tried to position myself so that I obstructed his view as much as possible.”

Another woman saw McCarthy masturbating when she was with her friend going from Highbury and Islington to Dalston Kingsland.

Sarah, again not her real name in order to remain anonymous, 26, from London, said: “I felt extremely angry and uncomfortable, I thought this man should not have been subjecting people to this and he should not be allowed to get away with it.

"I remember thinking that this man, if I didn’t report him, could go on to do more serious things."

Other incidents of exposure took place on trains on the Underground at Brent Cross, Oxford Circus, Morden, Clapham South and Waterloo and also at Watford Junction Station.

McCarthy was sentenced at Blackfriars Crown Court on April 25 after pleading guilty to six counts of outraging public decency and six counts of breaching criminal behaviour orders.

He was also in breach of a suspended sentence and has served 16 weeks’ imprisonment.

Siwan Hayward, Transport for London's head of transport policing condemned McCarthy's actions.

“The actions of McCarthy were demeaning, unacceptable and intimidating,” she said.

“We do not tolerate unwanted sexual behaviour on London's public transport and I commend all those who came forward to report what they saw."

British Transport Police investigating officer PC George James added: “I encourage anyone who experiences or witnesses unwanted sexual behaviour on the rail network to report it to stop it as soon as possible.”

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