"Well, it's been a whirlwind of emotions these past few days," he wrote. "I've been overwhelmed with feelings of anger and sadness and guilt.
"But, ultimately I find myself left with just a deep love and respect for Dylan. He is one tough cookie. I'm sorry for the grief this accident has caused his friends and family as well as my wonderful cast and crew."
"It's scary seeing your friend get hurt, but fortunately, Dylan is going to be just fine," he added.
"After a few weeks of rest and recovery he'll be back up and running to finish our adventure together."
Filming on the movie has been temporarily shut down as a result of the accident.
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"Dylan O'Brien was injured yesterday while filming Maze Runner: The Death Cure in Vancouver, Canada," a studio representative for 20th Century Fox told TheWrap.com on Friday.
"He was immediately transferred to a local hospital for observation and treatment."
Production on the film will be shut down while O'Brien recovers.
The Maze Runner: The Death Cure is still scheduled for release in February 2017.
- WENN