Rotherham could be facing action from the Football Association following a pitch invasion in Saturday's 2-1 win over Leyton Orient.
Alex Revell's goal in the fifth minute of injury time saw several fans enter the field of play and the FA are now investigating the circumstances.
A club statement read: "The Football Association have launched an investigation into how this happened and what Rotherham United propose to do to ensure this does not happen in the future.
"We appeal to supporters to contact the club if they have any information as to the identity of the individuals.
"Rotherham United take such incidents very seriously and anyone behaving in such a way can expect to have firm action taken against them.
"We will also assist South Yorkshire Police in seeking prosecutions for any criminal offences that may have been committed.
"The club understands that the last-minute winning goal provided feelings of strong emotions but we cannot allow supporters to enter the field of play at any time."
The Millers could face a hefty fine if the governing body decide to act.