The brother of a British engineer and his family who were killed in the French Alps said the arrest of a 48-year-old - believed to be a former policeman - in connection with the killing, is "better than nothing".
Saad al-Hilli and his wife Ikbal, from Claygate in Surrey, and her mother Suhaila al-Allaf, who lived in Sweden, were all shot dead on a remote forest road in Chevaline, near Annecy, on September 5, 2012. A local cyclist, Sylvain Mollier, was also murdered.
Last month Mr al-Hilli's brother Zaid al-Hilli, who was arrested in connection with the shooting, had his bail cancelled by Surrey Police after the force decided there was not enough evidence to charge him with a crime.
When asked if he was happy to hear about the arrest in France, he told Sky News: "Yes, I am happy, yeah."
Mr al-Hilli was asked whether this arrest, if it leads to a prosecution, would bring closure to him, to which he replied: "Well of course, I mean, anything is better than nothing. We'll see what happens. We can't raise our hopes."
Yesterday, French police arrested a man from the Haute-Savoie region of France in connection with the killings.
According to local media, the man is a former municipal policeman who lived close to the scene of the murders in Chevaline. Investigators were said to be looking into places he had frequented.
It has been claimed the man's mobile phone data indicates he was around the crime scene at the time of the killings, and weapons were reportedly found at his home.
Annecy prosecutor Eric Maillaud said the arrest followed the release in November of an artist's impression of a motorcyclist seen near the scene.
In a statement yesterday, he said: ''As part of the inquiry into the Chevaline killings in which four people were shot dead and a little girl was seriously injured, a 48-year-old man living in Haute-Savoie was brought in for questioning by Chambery police this morning and placed in police custody.
''This questioning, which may not be the only one, is the result of witness statements collected after the release on November 4 of an artist's impression of a motorcyclist seen near the scene of the crime who investigators were actively looking for.
''In the interests of the importance of presuming innocence and in the absence of a direct link between this man and those involved in the incident, no further information about his identity will be given.''
Surrey Police said the arrest came from a line of inquiry in France and not as a result of the investigation in the UK.
The murders were discovered by cyclist Brett Martin, who found Iraqi-born Mr al-Hilli, 50, his 47-year-old dentist wife and her elderly mother blasted to death in their BMW.
The al-Hillis' eldest daughter Zainab was shot in the shoulder and beaten, but survived. Her then four-year-old sister Zeena lay hidden under her mother's body and was only discovered eight hours after the murders.
Since the deaths, speculation has surrounded whether the shooting was linked to the al-Hillis' native Iraq, or Saad al-Hilli's work as a satellite engineer.
In November, police released an artist's impression of a motorcyclist seen riding in the area between 3.15pm and 3.40pm on the day in question.
The man's helmet was said by Mr Maillaud at the time to be ''very particular'' and one of only a few thousand models worldwide, with a bottom section which opened laterally to reveal the lower face.
French police said the only similar helmet on the market is made by GPA and is an ISR model.
The al-Hilli brothers were alleged to have been locked in an inheritance dispute centred on the £825,000 home in Claygate, Surrey, where Saad and his family lived after their mother died from a heart attack in 2003.
Zaid, who inherited half the property, claimed that in 2011 his brother began to demand his share of the house ''there and then'' and pinned him down during a row.
The two men never spoke again except through lawyers, but Zaid denied rumours that he had threatened to kill his brother.
He said he knew little about a Swiss bank account containing the proceeds from their father's business in Iraq and would not comment on claims that he attempted to access it using an expired card or tried to fake their father's will.