Published: Sep 24, 2012 4:57 PM EDT

TALLAHASSEE, Fla. (AP) - Lawyers for a Florida man say the state should halt his pending execution because he is likely insane.
    
An attorney for John Errol Ferguson wrote Gov. Rick Scott on Monday and asked him to delay the Oct. 16 execution so psychiatrists could examine Ferguson.
    
Ferguson, now 64, was convicted of murdering six people execution-style in a drug-related crime in Carol City in one of the worst mass killings in Miami-Dade history.  Ferguson was also convicted in the murders of two Hialeah teenagers who had been on their way to a church meeting in January 1978.
    
Ferguson's attorneys say that he has long exhibited symptoms of schizophrenia and has been plagued by hallucinations and delusions.
    
Ferguson is slated to die by lethal injection at Florida State Prison near Raiford.

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