A tattooed sex attacker has been jailed for subjecting a young woman to a “violent and extremely frightening ordeal”.

Elias Kajue, of Kilburn, pleaded guilty to an assault on a 23-year-old woman at Cricklewood railway station on August 31 last year.

The victim was waiting for a train at about 6am, when she was approached by Kajue in the ticket hall.

He tried to engage her in conversation, but she had asked him to leave her alone because she was tired and did not want to talk, she told police.

Kajue, 22, left but returned a few minutes later and began harassing her again.

He then pulled her to her feet and dragged her to the station subway where he forced her to the ground and sexually assaulted her before being disturbed by rail passengers coming off an arriving train.

Kajue left the scene on his bike, but was clearly captured by station CCTV.

Detective Sergeant Mark Barton, investigating officer from British Transport Police, said: “Kajue brazenly targeted a young woman who was waiting alone for an early morning train.

“Seemingly oblivious to the fact that his crime was being recorded on station CCTV, he subjected her to a violent and extremely frightening ordeal.”

Detectives began an investigation and analysed the camera footage, before issuing appeals for information. They received details from the Metropolitan Police that Kajue was a possible suspect and raided his Kilburn home where they found a red mountain bike.

As well as the bike, the victim also recalled a distinctive “scripted” tattoo on the inside of Kajue’s forearm. Police records showed he had two distinctive tattoos of ‘Loyalty’ and ‘Family’ on his arms, and he was subsequently positively identified by his victim in a video identification parade.

DS Barton said: “The victim showed great bravery throughout our investigation and provided detailed descriptions of her attacker, including his tattoo, which we were able to cross-check with video footage and the police national computer database.”

In interviews Kajue initially denied all knowledge of the attack and said he had a bad memory of the date of the offence, claiming the person on CCTV was not him.

DS Barton added: “All of the evidence — his tattoos and red bike in particular — pointed to Kajue as being the person responsible for this assault.

“It gradually became clear to him that he had little option other than to plead guilty.”

He was jailed on Friday at Southwark Crown Court for sexual assault and false imprisonment. He will have to serve a minimum of three years in prison before being considered for release.

Martin Grier, head of security for First Capital Connect, explained that CCTV was a vital tool in deterring and catching criminals.