They said he had no documents but claimed to be Sudanese and to have been born in 1987.
One of the wounded is in critical condition in hospital.
At least two people have been killed and multiple others injured after a man carried out a knife attack in the French town of Romans-sur-Isère, local media is reporting.
The French prosecutor's officer said the attack took place in a commercial area of Romans-sur-Isere.
French Interior Minister Christophe Castaner on Wednesday said over 350,000 people had been fined for flouting the government's tough lockdown since the order took effect on 17 March. It has not been handed over to counter-terrorism prosecutors.
Futures rise after selloff, weekly jobless number awaited
But others, especially older adults and people with existing health problems may get pneumonia and need to be hospitalized. Among the next milestones for investors is Friday's U.S.jobs report, which will likely show a sharp drop in payrolls.
The judicial police in Lyon are investigating while prosecutors evaluate whether or not to open a terrorism investigation.
The town is now under a coronavirus lockdown, although people are allowed out to buy essentials. The victims were likely carrying out their weekend food shopping on the street that has bakeries and grocers.
There have been a number of knife attacks in France in recent months.
A large amount of armed police arrested the suspect and firefighters and ambulances attended the scene.
The knife man shouted "Allahu Akbar" before stabbing people who were queuing to go into a bakery.