LEONARD Nimoy is currently receiving hospital treatment after suffering from severe chest pains.
According to TMZ, the Star Trek legend was taken to UCLA Medical Center in Los Angeles on Thursday 19 February.
The actor, 82, is famous for playing the role of Mr Spock in the long-running sci-fi series.
He has entered hospital a number of times over the last few months.
Last year, he revealed he was suffering from chronic lung disease, despite stopping smoking more than 30 years ago.
Symptoms of Chronic Obstructive Pulmonary Disease include coughing, chest infections and breathlessness.
Nimoy was recently pictured looking frail and using an oxygen cylinder as he was wheeled through JFK airport.
A spokesperson for the actor said: "We don't have any comment at this time."
Though he stopped attending Star Trek conventions in 2011, the franchise's star made a cameo as Spock in the 2013 film Star Trek Into Darkness, and made a number of guest appearances in the science fiction series Fringe, which ran until 2012.
Nimoy has played the famous Vulcan character since 1966 and was the only actor from the original series to return for JJ Abrams' recent film versions.
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