Conan O'Brien's On-Air Tribute to Robin Williams

"This is absolutely shocking and horrifying," he told his audience.

— -- Late-night host Conan O’Brien learned about the death of Robin Williams during the taping of his TBS show Monday.

The Oscar-winning actor and comedian was 63.

At the close of the episode, O’Brien discussed the death with his audience, as guest Will Arnett and sidekick Andy Richter sat nearby.

“This is unusual and upsetting, but we got some news during the show that Robin Williams has passed away,” O’Brien said, as the audience gasped.

“I’m sorry to anyone in our studio audience that I’m breaking this news, this is absolutely shocking and horrifying, and so upsetting on every level.”

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Richter acknowledged the performer’s loved ones.

“He was an amazingly kind and generous person, and it’s got to be a terrible time for his family, and our thoughts go out to them,” Richter said.

Arnett’s voice grew shaky as he discussed Williams’ death.

“As funny as he was, he’s truly one of the all-time greats – he was even better as a person, he was even more fantastic,” Arnett said. “Just the loveliest, sweetest, one of the kindest guys that I’ve ever worked with … just such a soft, warm, emotionally sweet guy, and it’s a major, major loss for everybody.”

O’Brien closed the show by addressing the sorrow around Williams' death.

“We’re just processing this information literally right at this moment, and so we are thinking about Robin’s family, we’re thinking about everybody he touched around the world throughout his life, we’re thinking about Robin tonight,” O’Brien said.

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