Irish Premiership side Larne has suspended John Herron and launched an investigation after an image of the player was circulated on social media appearing to show him in a t-shirt with a Pro-IRA slogan.
The club's move has been welcomed.
In a statement on Monday morning, Larne said the midfielder would play no part in their fixtures at any level during his suspension.
"Following the circulation of an image online yesterday evening (Sunday), Larne Football Club can confirm John Herron has been suspended with immediate effect," the club said.
"For the period of his suspension, John will not represent the club in fixtures at any level. An investigation into this incident is now underway.
"We have shown that we are an inclusive football club for all, demonstrated not only in words but also by our extensive work in the local community.
"There is no room for behaviour which falls outside of this ethos and we fully expect members, players and anyone associated with the club to reflect these standards at all times. "We will be making no further comment until the investigation has been completed."
DUP East Antrim MLA Gordon Lyons described the picture as "abhorrent" while UUP MLA John Stewart said Herron should never play for the side again.
East Antrim MLA Danny Donnelly welcomed the club's move.
Alliance representative Donnelly said: "I I welcome this swift action by Larne. They have a strong commitment to inclusivity at the club and a player publicly showing support for terrorism is not in any way compatible with that."
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