'Westworld' Actor Zahn McClarnon Sustains Serious Head Injury that Caused Production to Stop

Zahn McClarnon, who has a reoccurring role on the second season of "Westworld," sustained a very bad head injury earlier this week that landed him in ICU and caused production to stop ... sources tell TMZ.

Sources familiar with the situation tell us, Zahn fell at his home and hit his head. We're told the impact caused serious trauma and he was rushed to the ICU.

Our sources say Zahn is still in the hospital but is "on the mend."

TMZ broke the story -- production on the HBO hit was stalled after a cast member suffered a medical emergency off set -- but the actor's identity remained a mystery.

Zahn is known for his performance as Hanzee Dent on "Fargo," and his long running stint on "Longmire."

As for production on "Westworld," as of the time this story posted, it's still suspended.