Friday’s attack came three weeks after the start of a trial in Paris of alleged accomplices in the January 2015 attacks against Charlie Hebdo, a policewoman and a Jewish supermarket that killed 17 people.
While the man allegedly committed the stabbing alone, eight other people are now also under arrest after two other detentions on Saturday.
The two new people arrested were the suspect’s younger brother and another acquaintance, a judicial source said.
Those injured were employees of the award-winning television production agency Premieres Ligne, whose offices are in the same building in central Paris that previously housed Charlie Hebdo.
However, it is believed that the two victims, who took to the streets for a cigarette break, were not specifically attacked. They were seriously injured but their lives are not in danger.
The suspect mistakenly believed that the Charlie Hebdo offices were still in this building and wanted to attack the magazine’s journalists, a source said, confirming information first published in Le Parisien newspaper.
Charlie Hebdo moved its offices after the 2015 attack and its current address is being kept secret for security reasons.
French Interior Minister Gerald Darmanin said on Friday that the attack was “clearly an act of Islamist terrorism”. Counterterrorism prosecutors have opened an investigation.
Five of those arrested were in an apartment in Pantin, in the northern suburbs of Paris in Seine-Saint-Denis, the alleged last address of the alleged attacker.
The suspect arrived in France three years ago as an unaccompanied minor, apparently from Pakistan, but his identity was still being verified, the minister said.
Late Friday, police released another man who was close to the scene of the attack but was confirmed to be a witness who “pursued the assailant,” a judicial source said.
‘Could have done better’
Twelve people, including some of France’s most famous cartoonists, were killed in the attack on Charlie Hebdo’s offices by gunmen on January 7, 2015.
Charlie Hebdo angered many Muslims around the world by publishing cartoons of the Prophet Muhammad in 2006 and, in a defiant gesture, reprinted some of the cartoons before the trial.
In court are 14 alleged accomplices of brothers Said and Cherif Kouachi, the perpetrators of the 2015 attack on Charlie Hebdo which was claimed by a branch of Al Qaeda.
A policewoman was killed a day later, followed by the murder of four men during a hostage-taking at a Jewish supermarket by gunman Amedy Coulibaly the next day.
The magazine received further threats from al-Qaida this month after reposting the controversial cartoons.
Darmanin admitted the risk of an attack around the old offices had been “underestimated” and said he had demanded an explanation from the police.
“Obviously we could have done better,” he said.