While authorities initially thought two attackers were involved, they now believe it was only one person, who was detained near the Bastille plaza in eastern Paris, a city police official said.
The official said police are still searching the area while they question the arrested suspect.
Police initially announced four people were wounded in the attack but the official said there are in fact only two confirmed wounded.
It is unclear what motivated the attack on Friday or whether it had any link to Charlie Hebdo, which moved offices after they were attacked by Islamic extremists in 2015, who killed 12 people inside.
AP reporters at the scene of Friday’s police operation saw officers flooding into the neighbourhood, near the Richard Lenoir subway station.
Police cordoned off the area including the former Charlie Hebdo offices after a suspect package was noticed nearby, according the police official.
They did not release the identities of the attacker or the wounded, who are in “absolutely urgent” condition, the official said.
Prime Minister Jean Castex cut short a visit to a suburb north of Paris to head to the Interior Ministry to follow developments.
The trial in the Charlie Hebdo attacks is currently under way in the city.
Murmurs broke at the terrorism trial of 14 people accused of helping the attackers in the January 2015 killings as the news filtered through.
The widows of the Charlie Hebdo attackers are scheduled to testify on Friday afternoon.
