Published: Feb 06, 2011 1:07 AM EST
Updated: Feb 05, 2011 10:07 PM EST

FORT LAUDERDALE, Fla. (AP) - Lifeguards are warning swimmers to stay out of the waters off South Florida because Portuguese man-of-war.
      
Beachside cities in Broward and Palm Beach counties have reported the neon purple and blue sea creatures in their waters.
      
The man-of-war tentacles can deliver powerful stings that sometimes cause swelling and shortness of breath.
      
More than 20 people were treated for man-of-war stings near the Pompano Beach Pier on Thursday. Delray Beach Ocean Rescue has treated about 90 people for the stings since Wednesday.

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