The 61 year old was admitted to St. John's Hospital in Jackson, Wyoming to undergo tests for an abdominal infection.
The band had been due to perform at the Hard Rock Biloxi casino on Friday and Saturday but have now scrapped the gigs.
An update on the rockers' Twitter reads:
Our shows in Biloxi on 2/15 & 2/16 have been cancelled. Gary has been hospitalized We are awaiting further info. Thanks for ur understanding— Lynyrd Skynyrd (@Skynyrd) February 14, 2013
A rep for the casino adds, "Hard Rock Biloxi sends our thoughts and well wishes to Mr. Rossington and his family during this time."
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