Metz plans to take legal action against a far-right group of its fans who made Nazi salutes at the end of last week's league match against Lyon.
This latest extremist incident in the French league follows displays of racism at a Metz game on Feb. 16 and at a second-division match Friday involving fans of Corsican club Bastia.
The French soccer league (LFP) responded by asking players and officials from first- and second-division clubs to wear T-shirts bearing the message: "Racism ... Never again!" before last week's games.
After their 2-0 loss to league leader Lyon on Saturday, Metz players threw their T-shirts into a crowd of about 100 traveling supporters at Stade Gerland.
Metz director of security Jacky Ancel said about 10 of the club's fans responded with Nazi salutes.
"We will try and identify them and take legal action," Ancel said Tuesday.
Ancel said they are likely to belong to an extremist group of fans who call themselves "Identity Youth" ("Jeunesse Identitaire" in French). It is a branch within another far-right group of about 40 Metz fans who call themselves "The Faction" ("La Faction"), said Ancel.
"Within this small group (The Faction), there are a few Nazis associated with the extreme of the extreme right _ Identity Youth," Ancel said. They "are people who like to fight."
Ancel said Metz's options are limited because it can only ban the fans from games if they are caught red-handed breaking the law.
"You can ban someone from a nightclub, but we can't ban them (from a stadium). It's scandalous," he said.
French soccer league president Frederic Thiriez has criticized the lack of banning orders.
"Today in France we only have 80 people banned from stadiums," Thiriez said. "In England, there are 3,500. Thus, this law needs to be applied with much more severity."
On Friday, Bastia fans displayed a banner with racist insults before the match against Libourne Saint-Seurin. It was aimed at Libourne's Boubacar Kebe, who is black and from Burkina Faso.
The referee delayed the start by three minutes until the banner was removed. Bastia won 2-1.
Kebe refused to play Friday because he had been racially insulted by some Bastia supporters during a home match on Sept. 14, when he reacted with a gesture that led to him being sent off.
The LFP could dock points from Bastia.
It is also reviewing another racist incident involving Valenciennes captain Abdeslam Ouaddou, who led Morocco at the African Cup of Nations last month.
Ouaddou was racially abused at Metz's Saint-Symphorien stadium and climbed into the stands to seek out the aggressor, who has since apologized but faces prosecution. Ouaddou was calmed down by other Metz fans and he then withdrew.
Ouaddou says he alerted match referee Damien Ledentu several times before taking matters into his own hands, but the match was not stopped and Ouaddou received a yellow card for nonsporting behavior.
Ledentu denied Ouaddou alerted him to the racist insults, but has not taken charge of a match since.
Ouaddou has filed a complaint with police and the LFP has promised to file a legal complaint against the fan. Metz president Carlo Molinari said his club had also filed suit.