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
Microsoft's new system Windows 8 has been met with approval after its disastrous predecessor but users have yet to be entirely convinced.
Alton Towers crash victim Leah Washington, who lost a leg as a result of the horrific incident, celebrated her 18th birthday last night.
American Football's first female coach, Jen Welter, is hoping to be an inspiration across the globe after being hired by Arizona Cardinals