Published: Jul 25, 2013 5:12 PM EDT

PLANTATION KEY, Fla. (AP) - A Pennsylvania man is dead after becoming unresponsive while diving in the Florida Keys.
    
The Monroe County Sheriff's Office says it's not immediately known if the 52-year-old man was participating in the two-day recreational spiny lobster season on Thursday. One diver was reported dead during last year's mini season.
    
Authorities say the man was with two friends diving off Plantation Key when he became unresponsive. His friends performed CRP and the diver was later taken to the hospital where he was pronounced dead.
    
Sheriff's detectives are investigating the case. An autopsy will determine the cause of death.

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