Tributes have been pouring in for the late Fair City and Sons of Anarchy star Alan O'Neill, with his co-stars and fans taking to social media to pay their respects.

O'Neill's manager casting agent confirmed that the 47-year-old star had passed away in Los Angeles. A cause of death is yet to be announced, though there are reports that he suffered with heart problems.

His Sons of Anarchy co-star Timothy V Murphy was one of the first to pay tribute, tweeting his condolences to O'Neill's family.

Fans of O'Neill's work have also been taking to Twitter in reaction to the news of his passing, with one hailing his on-screen bromance with Mick Nolan's Ray as "Fair City's greatest bromance."

Others have shared memories of meeting O'Neill while expressing their sadness at his death.