LOUISVILLE, Ky. (WDRB) -- A fourth suspect has been arrested and charged with the murder of a man found dead inside a toolbox floating in a creek. 

59-year-old Melanie Howard was taken into custody on Friday, charged with murder, kidnapping, tampering with physical evidence, and unlawful imprisonment in connection with the murder of 29-year-old Tromain Mackall, according to Kentucky State Police. 

Howard joins three men also charged with the August 2016 murder. 29-year-old Marcus Boyken was arrested in December, joining 33-year-old Christopher Hill and 48-year-old William Howard Junior. 

Mackall's body was found in a toolbox floating in a creek in Grayson County nearly a week after his family says he seemingly vanished.

Howard is being held at the Grayson County Detention Center without bond. 

The investigation remains ongoing. 

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