reports how State Prosecutor Veronique Dizot now says they were the victims of an “unfortunate encounter”.
She said: “Why not consider the theory that they met someone who for some reason did not want their activities known, and whose personality led them to eliminate all the witnesses?”
Tourist Saad al-Hilli, 50, wife Iqbal, 47, and mum-in-law Suhaila, 74, from Claygate, Surrey, were shot dead near Annecy, France.
The couple’s two daughters survived.
Zeena al-Hilli, then four years old, was discovered hiding under her mum’s body hours after the shooting.
Her sister Zainab, then seven, was found with serious head injuries after being shot and beaten.
Also killed at the lay-by was 45-year-old French cyclist Sylvain Mollier.
The French lead prosecutor said it was the most complex case she had ever worked on.
The family were holidaying near Lake Annecy when they were attacked.
State Prosecutor Veronique Dizot added: “After five years, we are a bit discouraged and worried. Time is working against us.”
There have been numerous theories surrounding their deaths.
Mr al-Hilli’s brother Zaid was arrested and questioned about an alleged family feud but was later told he would face no further action due to a complete lack of evidence.
Other theories have speculated that the cyclist Mr Mollier, a nuclear industry worker, was the real target.
Zaid al-Hilli said: "There hasn't been any progress in the case. The initial investigation [by French investigators] has been a total failure.
"They made claims against the family which they couldn't prove."
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