Actor Alan O'Neill of Sons of Anarchy fame was found dead late Wednesday at age 47.
The body of the Irish entertainer, who played Hugh on the popular program, was found by his girlfriend in her apartment hallway, according to TMZ.
O'Neill, the outlet reported, had past battled drug and alcohol abuse, as well as heart problems, and was a cigarette smoker. Authorities did not suspect foul play in the actor's death, according to the outlet, and and results of an autopsy are pending.
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Gone too soon: Actor Alan O'Neill of Sons of Anarchy was found dead late Wednesday at age 47 at his girlfriend's apartment building, according to TMZ
He had appeared on the FX series during its sixth and seven seasons.
Other projects he'd worked on in his career, which dated back to the late 90s, included the TV shows such as Fair City and Inspector George Gently. He has a role in a yet-to-be-released horror film titled Charlie Lives: The Family's Return.
According to the casting company Castannettenow, O'Neill also had onstage experience in productions such as A Streetcar Named Desire, Hamlet, King Lear and The Importance of Being Ernest. The late actor was skilled in many fields including horseback riding, swimming, fencing and combat, the casting agent said.
Out and about: The actor was snapped at a 2014 screening of Sabotage in LA
On the tube: O'Neill (L) shared the screen with actor Charlie Hunnam on Sons of Anarchy
On Twitter, O'Neill's colleagues, friends and fans paid tribute to the late actor.
'My good friend Alan O’Neill died today....we worked together on The Sons Of Anarchy...my condolences to his family,' wrote actor Timothy V. Murphy.
Actor Seamus Power said, 'So sad to hear of the passing of Alan O’Neill who played "Keith" in Fair City. Always enjoyed working with him. Rest In Peace old pal.'
A fan running an account called Fair City Fans spoke to the actor's pleasant disposition: 'I met Alan O'Neill on the first #faircity [set] tour and he was so funny, genuine and a pleasure to talk to. Such a loss and so very young.'
Fondly remembered: On Twitter, O'Neill's colleagues, friends and fans paid tribute to the late actor
Sons of Anarchy actor Johnny Lewis died at 28 in September of 2012 after he fell off the roof of a building in the Los Feliz neighborhood of Los Angeles after murdering his landlady Catherine Davis moments before.
Authorities ruled the death of Lewis accidental, noting that Lewis (who was also known for dating Katy Perry) was not under the influence of drugs or alcohol in the deadly course of events.
Kurt Sutter, the creator of the program, took to Twitter following Lewis’ death, calling it 'a tragic end for an extremely talented guy, who unfortunately had lost his way.'
Sutter said he was not shocked by the course of events, and was 'deeply sorry that [Davis] had to be thrown into [Lewis’] destructive path.'