Very, very sorry to see this . . .
'MAZE RUNNER' STAR SEVERELY INJURED ON SET
'Multiple Broken Bones'
3/18/2016 11:27 AM PDT BY TMZ STAFF
Sources on the set tell us the 24-year-old -- who plays Thomas in the hugely successful franchise -- was filming a scene for "Maze Runner: The Death Cure" involving a car ... when something went wrong and he was run over.
We're told O'Brien was rushed to a hospital in British Columbia with "severe injuries" -- where he is currently undergoing treatment.
A spokesperson for 20th Century Fox tells us production will shut down while Dylan recovers.
Story developing ...