Jean-Michel Aulas has questioned the security arrangements in Marseille after the Lyon team bus was stoned prior to the Ligue 1 fixture at the Stade Velodrome.
Eleven people were arrested after trouble flared around the ground and Aulas, who was on the bus at the time of the attack, said more should have been done to protect the visiting players.
He told a news conference on Monday: "The bus was savagely attacked. I don't believe everything was done to protect the vehicle.
"We were travelling at a reduced speed on the Boulevard Michelet and in front of bars full of fans. And this [the attack] happened in front of one of them while we travelled in slow motion. No elementary precautions were taken."
Speaking about the incident on Sunday night, Aulas explained how the bus was left with a broken window and minor damage.
He added: "I was at the front of the bus. A paving stone came through the window.
"There were a lot of people hitting the bus with tools, some grabbed onto it, and the police had to use tear gas. It has nothing to do with real Marseille supporters, who know how to behave. Everyone was very, very afraid."