Blackpool Football Club has issued a statement after a video of a steward punching a fan was posted online.
The six-second clip shows a hooded man bursting forward towards stewards dressed in yellow vests and orange jackets.
As he is pushed back, one steward, who has a security ID badge strapped to his arm, punches him in the side of the head.
The short video was posted to Twitter after Blackpool's Leasing.com Trophy game against League Two side Scunthorpe last night, which the Seasiders lost 3-1, at Bloomfield Road.
The user wrote: "Is this how @BlackpoolFC are stewarding football games now??"
The video had been shared almost 200 times by this morning, with the club telling The Gazette in a short statement: “Blackpool Football Club is aware of an incident that occurred on the concourse at last night’s game against Scunthorpe United and is taking the matter very seriously.
“An investigation into the incident is now underway and the club will provide a further update in due course.”
It did not immediately say when asked whether the steward involved in the altercation will face disciplinary action.
Lancashire Police said in a statement: "We are aware of a video circulating on social media relating to an alleged assault at the Blackpool FC and Scunthorpe United FC match yesterday (Wednesday, November 27).
"We are looking into the matter. Anyone with information can contact police on 101, quoting 0324 of November 28."