A group of protestors descended on the training ground of Paris Saint-Germain on Thursday morning, according to AFP.
It is understood that 50 young people launched the attack as they broke into the Camp des Loges earlier in the week.
The 'fans' were reportedly members of the group of support of former president Robin Leproux, who relinquished control of the club in the summer.
Assistant coach Claude Makelele reportedly calmed the incident, with no reported injuries surfacing.