LONdon  - Actress Sadie Frost asked close relatives, including her mother, to sign confidentiality agreements because she did not know the source of tabloid stories about her, a court has heard.

The Mirror Group has admitted writing 27 stories about her between 2003 and 2006 after hacking her voicemail. She said it had been a ‘real relief’ to learn years later that those closest to her were not the source of the stories. Ms Frost, 49, told the High Court ‘my life was completely interfered with’. She also said she was ‘shocked’ to discover that Mirror Group Newspapers (MGN) had 35 invoices from private detectives who were employed to find private information about her. Ms Frost, the former wife of actor Jude Law, said her ex-husband had suspected her of selling stories about him to the newspaper group.

It was only in recent years that she realised their phones had been hacked, she said. She told the court Mr Law had subsequently said to her that if he had not thought that she was selling stories about him there would have been a ‘good possibility’ they would not have divorced. Ms Frost, who starred in the films Dracula and Love, Honor and Obey, now runs the fashion label Frost French.

Also on Friday, former MGN journalist James Hipwell told the court that phone hacking had been ‘endemic’ at the newspaper group and he had never seen anyone display ‘any moral qualms’ about doing it. He recalled that BBC creative director Alan Yentob had been a regular victim. Mr Hipwell said he had a ‘very clear memory’ of journalists singing a line from the Spike Milligan song ‘The Ying Tong Song’ when Mr Yentob's phone had been hacked, replacing the words ‘Ying Tong’ with the word ‘Yentob’.

Mr Hipwell, who received a six-month prison sentence in 2005 over the ‘City Slickers’ share-tipping scandal, denied a suggestion by Matthew Nicklin QC, for MGN, that giving evidence to the trial was the ‘ultimate payback’. Mr Hipwell said: ‘I believe it's the right thing to do, the responsible thing to do.’