A London commuter has been sentenced to eight months in jail for sexually assaulting two women and rubbing his genitals in front of strangers.

58-year-old Jamie Sierra-Ferrucho pleaded guilty to groping two women, aged 24 and 25, on the tube in January and February. The case has been described as "revolting" by the police and the victims said Sierra-Ferrucho even smiled while touching them below the waist. He appeared in front of Blackfriars Crown Court on December 15.

According to the British Transport Police (BTP), the first offence, which occurred on 25 January at around 10am, was on the Underground's Central Line between Bethnal Green and Holborn. The second offence was on 20 February and took place between Canning Town and Green Park on the Jubilee Line.

Sierra-Ferrucho also pleaded guilty to two counts of outraging public decency, which refers to him touching himself in front of other commuters. A 22-year-old woman snapped a picture of him in the act on March 14 on the Victoria Line, which prompted BTP to investigate.

A mother and daughter also reported Sierra-Ferrucho touching himself inappropriately on the Northern Line between Morden and London Bridge. This incident took place on 20 March at about 2pm.

DC Andy Parkinson of the British Transport Police said he was happy with the court's decision. "Sierra-Ferrucho is a serial sex offender who used the London Underground network to conduct his revolting deeds. Not only did he touch himself inappropriately in front of shocked passengers, he sexually assaulted two women.

"His behaviour was disgraceful and has absolutely no place on the London Underground network," Parkinson said. "I am very grateful to each of the victims who reported these incidents and supported the investigation.

Along with his prison sentence, Sierra-Ferrucho was given a 10-year sexual harm prevention order.