Last November, three men tried to rob Joe Lengel outside of the South Toledo gym that he owned.
When Lengel fought back, he was shot and killed.
Since then, more people were found to have played a role in the robbery and murder.
US Deputy Marshal Christopher Hodge says, "There were five persons named in the charges. Four of those persons are already serving prison terms right now."
The fifth suspect, 20-year-old Deitrekk Boone, is still at large, facing charges of aggravated murder.
Police say he played one of the main roles in the homicide.
Authorities are now offering a reward, and asking for help from the public to bring Boone to justice.
"$5,000 anonymously, to anybody that provides us information leading to the arrest of Deitrekk Boone," says Hodge.
It's believed that Boone has since fled the area, and could possibly be in Cleveland, Columbus, or Atlanta Georgia.
He has family in Atlanta.
Hodge says he narrowly evaded arrest in Cleveland ten months ago.
"We were told by sources that we had missed Deitrekk Boone by less than an hour in time," says Hodge.
Authorities say Boone's youth makes it harder for them to track him, because he has no bank accounts or credit cards.
Hodge explains, "A lot of times we can use some sort of trail to get the folks. But in this case, he has nothing. And he's just been running."
Officials hope that a unique tattoo on \Boone's left forearm, that reads "My Brother's Keeper" in cursive letters, is key to finding the fugitive.
Hodge says in thousands of investigations, he has never seen a tattoo that says that.
If anyone is caught helping Boone, they will face state, and possibly federal charges.
Boone is considered to be armed, and dangerous.