"There will be no further comment from the Club in relation to this matter until the investigation has been completed."
It is not illegal to possess laughing gas, or nitrous oxide, in Britain. The gas can induce a feeling of euphoria when inhaled.
Prior to Saturday's league defeat by Manchester United which confirmed Aston Villa's drop to the second tier, caretaker manager Eric Black had dropped Agbonlahor, who has scored once this season, saying he would spend the next two weeks on an individual fitness programme.
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This was not the first time during this campaign that the 29-year-old club captain and former England international has courted controversy.
Pictures emerged of him apparently smoking a shisha pipe after Villa's 4-0 loss to Chelsea on April 2. However, an investigation by the Premier League's bottom club resulted in no further punishment.
(Reporting by Shravanth Vijayakumar in Bengaluru; Editing by Gareth Jones)
