The death of one of Britain's richest women in her London home remains unexplained after an initial post-mortem proved inconclusive.
Eva Rausing, the 48-year-old wife of the heir to the £5.4bn Tetra Pak drinks carton fortune, was found dead by officers on Tuesday as they searched her home in Belgravia, one of London's most expensive residential areas.
It is reported that her husband, Hans Kristian Rausing, is being held by police in connection with her death. The 49-year-old heir, whose Swedish father helped transform Tetra Pak into a hugely successful manufacturer, was originally arrested on suspicion of possession of drugs on Monday. He is said to be receiving medical attention while in custody.
American-born Mrs Rausing and her husband have both had long-running and often public battles against drug addiction.
On Tuesday police said that further tests were being carried out on her body after an autopsy was inconclusive. Officers from the Homicide and Serious Crime division are now investigating the case "and the death continues to be treated at this time as unexplained," police said.
Mrs Rausing's family issued a statement saying they are "deeply saddened by the death of their beloved daughter". Her parents Tom and Nancy Kemeny said: "Eva was a devoted wife for 20 years and mother of four much-loved and wonderful children.
"During her short lifetime she made a huge philanthropic impact, supporting a large number of charitable causes, not only financially, but using her own personal experiences. "She bravely fought her health issues for many years. The family is devastated at her death and asks to be given privacy at this difficult time."
Her husband's family said: "Hans and Marit Rausing and their family are deeply shocked and saddened to hear of the tragic death of their daughter-in-law Eva Louise Rausing. They ask that their privacy be respected at this sad time."
In 2008 the couple were in trouble with the police over drugs but the prosecution was formally discontinued.
Mrs Rausing herself supported a number of charities that helped to fight addictions.
One of them - Action on Addiction - was among the first to express sadness over her death and praise her "wonderfully generous" support over the years.