Dion Williams, 27, is wanted for assault, reckless endangerment and gun charges stemming from a June 1 shooting that left 31-year-old Julius Johnson dead. The pair got into an argument in a salon just before shots rang out.
Johnson died from his injuries July 5, authorities said in a news release.
The Dover Police Department said Williams was arrested Friday in connection with the shooting. That same day, Williams was taken to the Kent County Court of Common Pleas, where he had an active arrest warrant. He was transferred to the Capitol Police Department and placed in a Georgetown prison.
On Monday, a Dover officer preparing a press release on Williams' arrest learned that he had been accidentally released after his Kent County warrant was cleared.
The Dover police statement said Williams was set free due to a "communication error by a Dover police officer," but did not elaborate. Williams' whereabouts were unknown as of Tuesday evening.