Ten months after his brother's murder in the French Alps, Zaid al-Hilli has moved from witness to suspect.
Detectives are seeking new leads in the case of the British family gunned down in the French Alps last September.
Brett Martin, the first witness who found the British family in the Alps has described the moment he came across the attack.
A 48-year-old man has reportedly been arrested by French police in connection with the investigation into the murder of four people in 2012.
On 5th September 2012, Saad al- Hilli, a British engineer, his wife Iqbal, her mother Suhaila al-Allaf and French cyclist Sylvain Mollier were all killed in the attack on September 5 2012.
Two sisters orphaned when their parents and grandmother were shot dead while on holiday in the French Alps nine months ago can be brought up by relatives, a High Court judge has ruled.
Mr Justice Baker has approved a plan for Zainab and Zeena Al-Hilli to be cared for by two members of their extended family following a private hearing in the Family Division of the High Court in London.
The girls' father Saad, mother Ikbal, Mrs Al-Hilli's mother Suhaila al-Allaf and French cyclist Sylvain Mollier were murdered by a gunman on a remote mountain road near Annecy in September 2012.
Mr Justice Baker has said the girls can be named in media reports but he has ruled that any detail of their whereabouts must remain secret.
The brother of a British engineer who was shot dead with his wife and mother-in-law in the French Alps has been bailed after being arrested and questioned by police.
Zaid Hilli was arrested yesterday on suspicion of conspiracy to commit murder after officers uncovered evidence to suggest he doctored documents to ensure he inherited the estate.
Hilli, 54, has previously denied any feud with his sibling over an inheritance or involvement in the killings.
A police spokesman said: "The 54-year-old man who was arrested yesterday on suspicion of conspiracy to murder has tonight been released on bail until July 31 pending further enquiries."
Detectives investigating a multiple murder in the French Alps last September, including a British couple, have arrested the brother of one of the victims.
French and British police have been working together to find the killer of Saad Al-Hilli, his wife, his mother-in-law and a French cyclist.
ITV News Europe Correspondent Emma Murphy reports.
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".
The brother of Saad Al-Hilli is being questioned by detectives investigating the killing in the Alps of Saad, his wife Ikbal, mother-in-law Suhalia al-Allaf and local man Sylvain Mollier.
Mr Al-Hilli's brother Zaid Al-Hilli, who is in his 50s and lives in Surrey, has previously denied any feud with his sibling over an inheritance. He was arrested by police at an address in Chessington.
Around 100 police officers in Britain and France are investigating the killing of the family on September 5 last year as they drove through a remote area close to Lake Annecy.
French investigators came to the UK and searched the al-Hilli family home in Claygate, Surrey, in the wake of the deaths.
They said in September that they were investigating three lines of inquiry, focusing on Mr al-Hilli's work, his family and links to his native Iraq.
Annecy's chief prosecutor Eric Maillaud said last year that there would be no ''quick solution'' in finding the killers.
Sources in France suggest the man arrested in connection with French Alps shooting is the brother of Saad Al-Hilli - Zaid. He was arrested at an address in Chessington on suspicion of conspiracy to commit murder
A man held by police in connection with the deaths of the Al-Hilli family in the French Alps last year has been arrested on suspicion of conspiracy to commit murder.
Surrey Police said the suspect, who they did not name was held at an address in Chessington at around 7.30am on Sunday "and is currently in police custody where he will be interviewed".
Surrey Police set up a Joint Investigation Team to work with French police on solving the brutal murders.
The al-Hillis' four-year-old daughter Zeena lay undiscovered under her mother's corpse in their BMW for eight hours after the shooting, while her seven-year-old sister Zainab was found with serious injures after being shot and beaten.
Surrey police said today's arrest was pre-planned and the result of on-going inquiries.
A 54-year-old man was arrested in Surrey today in connection with the murders of Saad and Ikbal Al-Hilli, Mrs Al-Hilli's mother Suhaila al-Allaf, and cyclist Sylvain Mollier, who were all shot dead near Annecy, in the French Alps in September last year, Surrey Police said.