2AM's leader was Jo Kwon went to the hospital for gas poisoning.

On Saturday March 23rd, the singer and actor was taken to the emergency room after inhaling gas while sleeping.

Jo Kwon was in his car, taking a nap, after pre recording for the MBC show “Show! Music Core,” and after being awakened by phone call, he felt dizzy with a bad head ache, was having difficulties breathing.

He went to emergency room, and was treated but the cause of his headache was not known. He then went back to tape the music show, and came back to the hospital for full check-up and they revealed he was mildly poisoned by gas.

The singer was apparently poisoned by a portable heater, which had a fuel container, that leaked the gas while he slept.

Jo Kwon let his fans know he was okay the next day when he Tweeted, “Thank you very much for your concern. I'm sorry for making you worry. I am resting at home now, and I feel much better . I will soon return with good health.”

Meanwhile, Jo Kwon will appear on his first drama, the KBS drama “The God of Workplace” premiering on April 1st, and also will appear in the musical “Jesus Christ Superstar” starting April 27th.