The game on December 3 at Metz's Stade Saint-Symphorien was abandoned in the 31st minute following the incidents, which came after Gauthier Hein had put Metz 1-0 up with a superb goal.
Portugal international Lopes was subsequently taken to hospital where he was diagnosed with "acoustic trauma".
"Considering the serious of the events, Metz will lose three points with one point suspended and the match will be replayed behind closed doors," said Sebastien Deneux, president of the disciplinary commission of the country's professional football league (LFP).