Floral tributes have been left outside the London home of Eva Rausing following the discovery of her body on Tuesday.
ITV News understands that Eva's husband Hans Kristian Rausing, the heir to the Tetra Pak drinks carton empire, is continuing to receive medical treatment after being arrested in connection with her death.
Mr Rausing was arrested after Eva's body was found at the couple's home in Cadogan Place, Chelsea.
Mr Rausing, who stands to inherit a billion-pound fortune from his father's business, was taken into custody at a south London police station but has since been moved to a "medical facility", police said.
Scotland Yard would not confirm the name of the suspect, but said a 49-year-old man was arrested in south London on Monday morning on suspicion of possession of drugs.
Police are treating Mr Rausing's death as "unexplained".
Hans and Märit 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.
Tom and Nancy Kemeny along with all of their family are deeply saddened by the death of their beloved daughter, Eva Louise Rausing. Eva was a devoted wife for twenty 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.
ITV News understands that Hans Rausing, one of UK's richest men and heir to the Tetra Pak drinks carton empire, has been arrested in connection with his wife's death after her body was found at their home in London.
In a statement, the police have said:
The man - who was further arrested in connection with the death whilst at a south London police station - is no longer at a police station, but is currently receiving medical attention. We are not prepared to discuss further regarding that matter.
Officers from the Homicide and Serious Crime Command are investigating, and the death continues to be treated at this time as unexplained.
On the morning of Monday 9 July a 49-year-old man was arrested in south London on suspicion of possession of drugs. Following a subsequent search that afternoon of an address in Cadogan Place SW1, a body was found.
Police have now confirmed the identity of the deceased as Eva Kemeny [her maiden name], of that address.