- Hans-Kristian Rausing's wife is found dead after he is arrested on drugs charges
- An autopsy fails to determine the cause of death, police say
- Rausing's father is worth an estimated $10 billion
(CNN) -- The son of one of the world's wealthiest men has been arrested after his wife was found dead in London in unexplained circumstances.
Police stumbled upon the mystery when they arrested Hans-Kristian Rausing on drug charges on Monday.
A search of his home after the arrest uncovered the body of his wife Eva, 48.
An autopsy on Tuesday failed to determine the cause of her death, police said Wednesday.
Police refused to name Rausing as the man who was arrested, but a source familiar with the investigation said the man in custody lived at the address where the body was found.
The source asked not to be named discussing an ongoing investigation.
The couple were arrested on charges of having cocaine and heroin in 2008, but avoided prosecution, Forbes magazine said in its annual rich list report this year.
Rausing's father is worth an estimated $10 billion, according to Forbes magazine, and his grandfather founded the Tetra Laval packaging business.
