Police in Britain have arrested a man on suspicion of conspiracy to murder a British family of Iraqi origin killed in southern France last year.

"The 54-year-old man was detained at an address in Chessington, Surrey ... and is currently in police custody where he will be interviewed," police said in a statement.

There were no further details of the suspect.

Some British media reported, however, that the suspect is the victim's brother.

One survivor

Husband and wife Saad and Ikbal Al-Hilli, also from the county of Surrey, in southern England, were killed in September 2012, along with Ikbal's mother, Suhaila al-Allaf.

They were found a remote mountain road near the French town of Annecy, close to the Swiss and Italian borders.

Their deaths prompted a joint murder investigation between British and French authorities.

A French cyclist, Sylvain Mollier, was also found dead near the scene.

The pair's four-year-old daughter survived the attack, spending several hours cowered among the bodies of her dead parents and grandmother.

The couple have one more daughter; both are currently in the care of a foster family.

Aljazeera