Johnson said based on the evidence in the notes they have issued an arrest warrant for Robert Shane Lucas, age 51, "for first degree premeditated murder." Lucas is Brewer's son-in-law.
"He was planning to commit a homicide and commit acts of violence against the family at that address," Johnson said of the information in the notes. He added that he could not discuss motive at this time.
Brewer's body was found under some household items in the garage after the Sheriff's Office executed a search warrant.
The cause of death was believed be blunt force trauma but an autopsy is pending.
Brewer had last been seen on Sunday, according to family members.
Johnson said Lucas was probably still in the Navarre or Gulf Breeze area and is considered armed and dangerous. He asked anyone with information to call 850-437-7867, the crime stoppers hotline.
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