The driver of the truck that fatally hit a 25-year-old man riding an electric scooter was under the influence of drugs at the time of the accident, Paris' prosecutor's office told Euronews.
The incident took place on Monday at around 10:30 pm CEST in the 18th arrondissement in a neighbourhood known as the Goutte d'Or.
The victim was taken to a hospital after suffering a cardiac arrest where he died of his wounds, firefighters told AFP news agency.
An investigation was opened on Thursday for "manslaughter by a driver of a vehicle after drug use," the prosecutor's office said.
Paris started cracking down on electric scooters earlier this month after an anarchic year in which startups flooded the city's streets with their vehicles.
The French capital has 12 free-floating scooter operators, more than the entire United States, according to a study released on Thursday, and about 20,000 of the two-wheeled vehicles.
The city's sidewalks have become something of a battleground between riders and pedestrians.
Mayor Anne Hidalgo and police want to limit speeds to 20 kilometres per hour (12 mph) in most areas, and 8 kilometres per hour (5 mph) in areas with heavy foot traffic, and prohibit parking anywhere but designated spaces.
The Swedish Transport Agency called to ban electric scooters from the road after a 27-year-old man died in a crash while riding one of the electric vehicles in May.