Emergency crews suspended their search at approximately 7 p.m. for a man who fell off a barge into the Ohio River near the Markland Dam.
Gallatin County dispatchers didn't know if search crews were going to continue Friday.
Authorities spent Thursday afternoon attempting to retrieve the person.
According to the Gallatin County Sheriff's Office, the incident was first reported around 10:10 a.m.
Information about the person's identity and the status of the rescue effort was not immediately publicized.
Boone County deputies confirmed their office had dispatched a water rescue team to help Gallatin County responders at the scene.