Armed robbers attacked an armoured vehicle in the southeastern city of Lyon on Friday, making off with 9 million euros in cash.
The vehicle was attacked on Friday morning by several armed individuals as it was exiting a Bank of France branch in Lyon.
Two vans blocked the armoured van, one in front and one behind.
According to prosecutors, the robbers threatened the driver, took the money, and fled in the two vehicles that were later found burnt.
No one was injured in the attack.
Locking system at fault
Chief executive Michel Tresch of Loomis security called the attack 'audacious'.
According to two colleagues of the attacked security team -- two men and a woman -- there have been repeated problems with the security vehicles' locking system.
While the security code is supposed to be changed for each run, the attacked vehicle had a 'permanent code' which saved time for the robbers, they said.
"There is clearly a fault on the part of the company," one told AFP, stressing that the driver of the attacked vehicle was a former shooting instructor trained in 'defensive driving'.
An enquiry was swiftly opened by police and regional specialists.
Swedish security firm attacked several times
Cash handling Swedish company Loomis has been attacked several times over the years.
Loomis chief executive Tresch said that compared to the 2000s, there were now fewer physical attacks.
"It is a lot easier to carry out attacks [on the internet] via hackers, as opposed to attacking an armoured vehicle," Tresch said.
The theft in Lyon is believed to be the biggest such cash heist in France since notorious robber Toni Musulin in 2009 made off with 11.6 million euros, most of which was subsequently recovered.