A waiter, Amine Belkacem, 50, who was serving diners in a Moroccan restaurant, said he saw young people running away from the scene. He asked them what was going on, and they told him they had heard shots and fled.
Mr. Belkacem said he then saw a man running down the street who tried to stab someone in a taxi.
Jules, 17, who refused to give his last name, was waiting in line outside a Japanese restaurant with his mother and aunt, when he heard shouts. He rushed inside the restaurant, where customers were already hiding under the tables.
A few minutes later, he said, he saw three police officers rush toward the assailant, who took a knife out of his pants’ pocket.
“I was so scared, I put my head on the floor,” Jules said, adding that he did not see what happened next. “I’m so shocked. I don’t know how I’ll be able to sleep tonight.”
Milan Charollois, 19, who lives on a street adjacent to where at least one of the stabbings took place, was coming home when people told him that a woman had been stabbed. He rushed to the scene and saw a woman he thought was probably in her 60s, who had been stabbed in her leg and near her neck. She was pale and people were gathered around her pressing their hands on her neck where blood was coming out, he said.