COLUMBIA, S.C.—Investigators have determined that former University of South Carolina football player Kenny Miles was not being robbed when he was shot in a parking lot near Columbia.

Richland County Sheriff Leon Lott said Tuesday that his deputies still are not sure how the 23-year-old running back ended up with a gunshot wound to his upper arm Monday.

"At this point we know Kenny Miles was shot. Where he was shot, why he was shot and how he was shot, we don't know," Lott said.

Miles was shot around 1 p.m. at an industrial park on a dead-end street just off Interstate 26 near Irmo. He initially told deputies a man was trying to take his championship rings and money.

The investigation and statements from Miles led deputies to determine the original story was false, Lott said.

Lott said it doesn't appear anything was taken from Miles. He refused to say if Miles was continuing to cooperate with deputies or why he might have made up the story about being robbed.

"I'm not real happy with the resources and time we spent on this case chasing false leads," Lott said.

No charges have been filed and the investigation continues.

Miles is expected to be released from the hospital Tuesday. A phone number for him could not be found.

Miles played high school football in Lawrenceville, Ga., and spent most of his career with the Gamecocks backing up Marcus Lattimore. He ran for 1,341 yards on 315 carries.

In his senior season in 2012, Miles ran for 359 yards on 104 carries as he got significant playing time after Lattimore was injured. The best game of his career came when he ran for 127 yards and a touchdown against Wofford. Miles scored two touchdowns in South Carolina's 2011 Capital One Bowl win over Nebraska.

Miles graduated with a degree in criminal justice.