By Etienne Ballerini
NICE (Reuters) - Nine people were injured when St Etienne fans threw seats at the local supporters at Nice's Allianz Riviera stadium on Sunday, the French interior and sports ministries said.
An hour before the kickoff of the Ligue 1 game between Nice and Les Verts, the away fans dismantled their seats and threw them towards the opposition supporters.
Stadium stewards unsuccessfully tried to calm them down, with police then moving into the stands to remove the St Etienne fans, who numbered about one hundred.
"Manuel Valls, the ministry of Interior, and Valerie Fourneyron, the sports ministry, condemn with severity the serious incidents that occurred before the Nice v St Etienne Ligue 1 game kickoff and during which nine were injured," the ministries said in a joint statement.
Nice security officer Andre Bloch told reporters eight people, including two stewards, had been injured.
"I am angered by what happened," Nice president Jean-Pierre Riviere told reporters.
St Etienne coach Christophe Galtier told a news conference: "Who is right? Who is wrong? I don't know. A stadium must not be a place where you settle a score. It must be a festive place."
The French League threatened a ban on travelling fans after the incident.
"Enough! The few cretins who claim to be supporters do not even realise they ruin the image of football," the French League (LFP) president Frederic Thiriez said in a statement.
"I will ask a meeting with the ministry of Interior to discuss the supporters' trips to away games.
"If we don't succeed in resolving this problem it will end with a systematic ban on (supporters') trips, which nobody wishes."
St Etienne won the game 1-0.
(The story corrects name of Nice's stadium in first para.)
(Reporting by Julien Pretot; Editing by Alison Wildey)