The family of honeymoon murder victim Anni Dewani say they've been through four years of "hell".

Anni's husband Shrien, the British businessman - accused of plotting her death - has walked free from a court in Cape Town.

Judge Jeanette Traverso dismissed the case against him, after evidence from prosecution witnesses was described as being "riddled with contradictions".

Ms Dewani's sister Ami Denborg was in tears as she spoke to Sky News outside the court in Cape Town.

And later, Ms Denborg and her brother Anish Hindocha explained why the family was so distraught that a judge had decided to throw out the case against Mr Dewani without him even being called to give evidence.

"We don't care if he's innocent or guilty, we just want to know what happened to Anni," said Ms Denborg.

"The only way to find out was to hear Shrien under cross-examination under oath telling his version of events. That right has just been taken away from us.

"We've been patient because we had hoped we'd get to the truth but today we just don't know what to think - we were so disappointed and so sad because this means we'll never, ever get to find out."

Asked how the family had coped since Anni was murdered in 2010, her brother added: "It's been very tough for our family. We've had four years of hell, literally.

"To see my parents wake up at 3am or 4am every day is a nightmare. What we're trying to do is be strong in front of them but it's been very difficult to cope with."

After the trial collapsed, Ms Denborg struggled to contain her emotions as she read a family statement.

Her brother collapsed in tears as she said: "The knowledge of not knowing is going to haunt us for the rest of our lives.

"We had four years of sleepless nights and we will never be able to sleep."

Mr Dewani had declared himself a bisexual on the first day of his trial - something Anni and her family had not known.

Her uncle Ashok Hindocha said Ms Dewani would never have agreed to the marriage if she had known about her husband's "secret sex life" and confirmed the family would speak to lawyers about bringing a civil case against Mr Dewani in the UK.

Mr Hindocha added: "As far as Anni's grief-stricken parents are concerned, they would not wish the torture they have endured onto any other mother of father.

"They will live forever with the warm and magical memories of Anni, but these memories will always be tinged with the pain of the fact that closure has not been afforded them."

Mr Dewani's family hugged and cried tears of joy after the verdict was announced.

A relative who spoke through the intercom at the family's home in Bristol told Sky News: "We are very happy."

Nathi Mncube, a spokesman for South Africa's National Prosecuting Authority, said he believed the authorities were right to pursue the case, despite anger at the amount of taxpayers' money spent to bring Mr Dewani before the court.

He said: "Obviously, we are very disappointed with the outcome today. When we started with the trial this is not what we set out to achieve.

"We believed there was evidence, otherwise we would not have taken the case to court."

Emotions were also running high on the steps of the courthouse, where a lobby group chanted: "Justice for Anni."