Rocker Bret Michaels remains in the hospital Tuesday morning after undergoing emergency surgery, RadarOnline.com can report.

The former front-man for Poison -- and current star of NBC’s Celebrity Apprentice -- was about to perform at Sea World in San Antonio, Texas on Sunday night when he was rushed to the hospital.

Michaels, 47, had been suffering all day from severe stomach pains, but thought he had a bad case of the flu.

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• Sea World
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