Arsenal have released a statement confirming that they will issue warnings to some of their star players after a video emerged showing them allegedly inhaling nitrous oxide.
CCTV footage published by The Sun appears to show Mesut Ozil, Pierre-Emerick Aubameyang, Alexandre Lacazette and Matteo Guendouzi using laughing gas, or "hippy crack," at a party in August.
In a statement, Arsenal said: "The players will be spoken to about this and reminded of their responsibilities as representatives of the club."
The Sun said the party took place shortly before the start of the season at the nightclub Tape in London, while Shkodran Mustafi and Henrikh Mkhitaryan also attended but were not pictured inhaling from the balloons.
Nitrous oxide is not illegal in Britain but experts say recreational use can be dangerous, especially if combined with alcohol.
Then-Liverpool player Raheem Sterling was warned for using the substance in 2015; Tottenham's Kyle Walker apologised for a similar incident in 2013. Both players later moved to Man City.
After losing the first two games of the season, Arsenal are on a 20-game unbeaten run under first-year coach Unai Emery ahead of Saturday's home game against Huddersfield in the Premier League.