French police have been left puzzled after cocaine-filled packages have kept washing up on beaches along the Atlantic coast for weeks.
Tides reportedly started washing up the packages a month ago on beaches stretching from Nantes to as far south as Biarritz.
According to the prosecutor's office in Rennes, new packages continue to arrive daily and the cocaine is dangerously pure.
More than 750kg of cocaine - most of it 83 per cent pure - was beached in plastic packages near the city.
Members of the public are being urged not to touch any packages they find and call police immediately.
The prosecutor’s office said in a statement: "Suspect packages have been found on all beaches ... from the Loire-Atlantique department down to the Landes department [a strip of coast of more than 500km].”
Rennes prosecutor Philippe Astruc told the BBC the 763kg of cocaine found on beaches "probably comes from South America, and it is worth very large sums of money".
He told France 2 TV: “It’s a very pure product that must not be consumed in this form because there is a very high risk of overdose. There is absolutely an immediate health risk.”
Police are investigating whether a drug trafficker's boat hit a storm or ran into trouble and released its cargo.
Sud Ouest newspaper reported two people discovered two packages on the beach in Arcachon, south-west of Bordeaux, on Friday containing 3kg of cocaine labelled “diamante” or “brillante”.
Packages reported to have washed up in Florida during Hurricane Dorian in September were also labelled "diamante".
The prosecutors are reportedly liaising with the US Drug Enforcement Administration and European anti-narcotics police in their investigation.