Arsenal are taking reports striker Alexandre Lacazette inhaled nitrous oxide from a balloon 'seriously' and will deal with the matter internally.
The Frenchman, who has been warned about a similar offence previously, was pictured with a balloon in his mouth and is said to have sent a video to friends, according to reports in the Daily Star.
An Arsenal spokesman said: 'This is a private matter which we are taking seriously. It will be handled internally.'

Arsenal are to deal with striker Alexandre Lacazette internally after he was seen appearing to inhale from a balloon with the club announcing that they are taking the matter 'seriously'

Footage published by The Daily Star appears to show the French striker filming himself at home seemingly inhaling from the balloon, which is in his mouth.