Sources on the French side of the team investigating the murders say it is a matter of asking questions of Zaid Al-Hilli on his feud with his brother, their father's inheritance and their father's money in Switzerland.
He is in custody as a result of moving from being a witness to a suspect. We are told they have no more elements of proof at this stage.
On Wednesday it was made very clear that Zaid Al-Hilli was not a suspect, although I was told "this could change at any time".
More top news
A Branislav Ivanovic header in extra-time ensured that Chelsea are through to the Capital One Cup Final after beating Liverpool
Scientists have discovered the oldest known earth-size planets discovered which they say raises the prospect of 'ancient life'.
Auschwitz survivor Alina Dabrowska was a victim of the cruel experiments of Nazi doctor Josef Mengele, known as "the Angel of Death."