However, after RAW went off the air, fans were later told that Lawler's condition had "stabilized."
"Lawler suffered a heart attack while commentating during last night's broadcast of Monday Night Raw in Montreal," read a statement on WWE's website. "We are hopeful Jerry makes a full recovery and returns to WWE in the near future. Our thoughts are with Jerry and his family."
According to co-host Michael Cole, Jerry was given CPR in the locker room of the arena before taken to the hospital. The 62-year-old was breathing on his own, but was in "an extremely serious situation."
"This is not part of tonight's entertainment," Cole said. "This is a real-life situation."
Meanwhile, Lawler's girlfriend Lauryn Laine McBride posted a statement on her Facebook page about his medical condition:
"Thanks everyone for your thoughts and prayers. It has been confirmed that Jerry did have a heart attack...he is in stable condition and breathing on his own & heart is stable. I'm getting on the first flight out of here to be with him & will keep everyone posted. He is a strong man and we will get him back at his best as soon as I can get him home! I love you so so much baby!!"
Twitter was also gone wild with tweets from Lawler's fans and friends, including his long-time broadcast partner, Jim Ross.
"I'm shaken by the news of my friend Jerry Lawler's medical emergency in Montreal. Hands shaking. Prayers for the King. I feel helpless," Ross tweeted.
There were some Twitter users who said that Lawler's heart attack was just part of the show. But Ross hit back and said:
"4 skeptics, @JerryLawler heart attack was REAL. NOT showbiz. He's in cardiac ICU in Montreal. My friend will 'kick out.' Believe it. I do," said Ross.
"I hope Jerry "The King" Lawler will recover from his heart attack & get well soon," tweeted James Acevedo.
"Hope Jerry "The King" Lawler pulls through, he and Jim Ross were the voice of my childhood," tweeted Adam Stockinger.
Lawler, who made his name in wrestling in the 1970s by winning multiple regional championships in Memphis, Tennessee, and the Mid-South Wrestling circuit, was introduced into the Connecticut-based WWE's Hall of Fame in 2007, CNN reported.
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