A representative of the actor revealed, "Because of the consecutive days of late night filming, overworking, his lymph nodes were swollen to the point where he couldn't breathe. But he returned to filming after he received an IV drip at the hospital despite also having lost his voice." 

The representative also commented further, "He is at a state where he needs rest but because he does not want it to affect the filming, he is fighting on. Especially because there are other actors who are also injured because of their action scenes. He is to depend on medicine and focus on filming for now."

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Park Hae Jin is currently playing the chilling role of the psychopath Lee Jung Moon in 'Bad Boys'.