A convicted child abuser has been given a four-year jail sentence for sexually assaulting two teenage girls on the Luas while en route to a Rihanna concert.

John Daly from Cabra Park, Phibsboro in Dublin had pleaded guilty to two charges of sexually assaulting the girls aged 13 and 16 in October 2011.

Two years of the four-year sentence were suspended.

The 53-year-old had previously pleaded guilty to attempted rape and indecent assault charges relating to two young girls in the 1980s and to aggravated sexual assault and sexual assault on a 62-year-old woman on dates from 1997 to 1998.

Today, Daly was sentenced for assaulting the two Limerick girls who had been driven to Dublin by one of their fathers for the concert.

He put them on the Luas at Heuston Station because of heavy traffic.

The two girls got separated on the busy tram.

John Daly approached the 16-year-old and molested her by putting his hand between her legs over her clothing.

The teenager later told gardaí she felt she had no way out because she was squashed against a bar and did not know how to deal with the situation.

The court heard today that she was shocked and frozen and because of the shock she was unable to do anything.

Daly then placed his hand on the 13-year-old's backside area for some time after she bumped into him and apologised for standing on his toe.

She said she moved out of his way at her first opportunity to do so.

Both girls gave a good description of Daly to the girl's father when they met him on the platform when they got off the Luas.

Daly became a suspect after gardaí viewed CCTV footage.

He was arrested three months later as he was about to board a Luas at the 02 following a One Direction concert.

During a garda interview he admitted he had got on the Luas heading for the Rihanna concert in order to touch young girls.

He said he wanted to apologise to the girls for what had happened.

Sentencing Daly, Judge Mary Ellen Ring said in a victim impact statement one of the girls said she felt uncomfortable meeting strangers on public transport and is more afraid generally.

Judge Ring said to be sexually assaulted in a public place when they were unfamiliar with the area can be a damaging event.

She said this was not an opportunistic spur of the moment assault but there was an element of some planning which is a matter of concern for the court.

She sentenced Daly to four years in prison but suspended the last two years.

She said it would be in everyone's benefit that he receive treatment and ordered that he attend the Safer Lives Programme.

In February 2000, Daly was sentenced to three years in prison with one year suspended for attempted rape and aggravated sexual assault charges.

The DPP successfully appealed the leniency of the sentence and it was increased to a six-year term.