Veteran entertainer Rolf Harris has been found guilty of a string of indecent assaults against underage girls.

Harris, whose showbiz career spans more than 60 years, was impassive as the jury returned guilty verdicts on all 12 counts after a seven-week trial at Southwark Crown Court in London.

He will be sentenced on Friday. Justice Sweeney warned Harris it was "inevitable" a custodial sentence would be possible.

It is the highest profile conviction achieved by officers from Scotland Yard's Operation Yewtree team - the unit set up to investigate historical sex abuse claims in the wake of the Jimmy Savile scandal.

During the trial, four females described their ordeal at the hands of Harris - with the youngest being just seven or eight years old.

He was accused of indecent assaults dating between 1968 and 1986, but several other women gave bad character evidence against him at the trial - reliving how they had been molested by him as late as 1991.

Prosecution sources have confirmed that dozens of other women have also come forward during the trial claiming they too were also assaulted by him and police are considering whether to bring further charges.

The main complainant against Harris was the best friend of the Australian born cartoonist and singer's daughter, Bindi.

The woman (now 49) told how she was first molested by Harris after she stepped out of a shower during a holiday in Hawaii in 1978 with Bindi and the rest of her family.

He then groped her again on the beach before carrying out further attacks on her in the bedroom of his family home in Australia - as Bindi slept nearby - and the assaults continued back in Britain.

Prosecutor Sasha Wass described Harris as a ''sinister pervert'' who used his fame to get close to young women and girls adding that he had a ''dark side'' and was a ''Jekyl and Hyde character''.

Key to the case was a letter written by Harris to the father of the main victim in 1997 after she had told her parents of the abuse she had suffered as a teenager.

In it, Harris wrote how he was in a ''state of abject self-loathing'', adding he was ''sickened'' by the ''misery I have caused".

The prosecution said it amounted to a confession of his indecent assaults on her and which went on until she was 29 - only ending when she moved to Norfolk.

Reporter Rhiannon Mills, who is  outside court - says the most serious charges related to the best friend of Harris' daughter.

The other allegations involved attacks on a girl in Portsmouth in 1968-1969, a woman in Cambridge sometime between 1975 and 1979 and an Australian woman called Tonya Lee, who was molested in a London pub in 1986.

In an interview broadcast last year Ms. Lee said ''I don't know how he lives his life day to day, and I don't know how he sleeps at night".

Countless generations of children and adults know him through iconic programmes from the 70s, 80s and 90s, such as 'The Rolf Harris Show', 'Rolf Harris Cartoon Time', 'Animal Hospital' and 'Rolf On Art'.

His wife of 56 years, Alwen, and daughter Bindi (49) supported him in court throughout the seven-week trial, although only Bindi was called to give evidence in the case.

She described how she wanted to ''stab herself with forks'' after discovering Harris had been having a relationship with her best friend, who was the subject of seven of the charges.

In his 2001 autobiography, titled after his catchphrase "Can You Tell What It Is Yet", there is a telling passage in which he explained his feelings about his family.

He wrote ''Alwen and Bindi have to come first. It has only been in the last five years that I have realised this. Late, but better than never".

Telling, because it was in 1997 Harris wrote to the father of Bindi's best friend to tell him of the affair he had been having with his daughter when his own daughter found out.

He also wrote of how, as his career took off in the 60s, he found himself ogling women in backstage dressing rooms set aside for dancers he worked with.

Harris wrote ''I tried not to watch - or be seen watching - but it wasn't easy, I spent most of my time reading the same page of a book 14 times realising I was holding it upside down".

It is also clear he had a difficult relationship with his daughter and wife - blaming himself for not being with them as he devoted his time to his career - leaving them a painful second.

In the early 1960s as his career hit the big time, Alwen visited Australia with him and it later emerged she had contemplated suicide, Harris only finding out about it 30 years later when he found her diary.

Harris described how ''the words struck me like hammer blows'' adding that he ''felt terrible and I kicked myself for my selfishness''.