DeJuan Hammond, 34, was accused of hiring Steven Pettway to kill Troya Sheckles in a bold daylight shooting in Shelby Park in 2009.
Sheckles had been scheduled to testify against Hammond's brother, Lloyd, but was killed before she could. Pettway was convicted in the case and sentenced to 55 years in prison.
The Hammond brothers have denied any involvement in the killing.
Ike Kinnison and Don'teze Hurt, both of whom testified at Pettway's trial in July, were slated to testify at DeJuan Hammond's trial in Sheckles' death, but have both disappeared, forcing prosecutors to drop the charges against the suspect, The (Louisville) Courier-Journal reported Thursday.
Prosecutors said Wednesday that they will refile the charges if the witnesses resurface.
Hammond will not be released from jail, however, because he is facing other charges, said Leland Hulbert, a spokesman for the Jefferson County commonwealth's attorney's office. He is facing charges of drug trafficking, wanton endangerment and tampering with evidence, attempted murder, kidnapping, assault, burglary and other felonies.
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