Rescuers searching the Ashley River for a boater missing since Sunday have found no sign of him, authorities said Tuesday.

Preston Guyse, 26, reportedly launched his boat for a test run Sunday morning and the boat tilted, causing Guyse to fall into the water.

North Charleston police spokesman Spencer Pryor said Tuesday evening that Guyse had not been found.

The search has concentrated in the area near Duncan’s Boat Harbor.

Among agencies reportedly involved in the search are the S.C. Department of Natural Resource, which put divers in the water, and the North Charleston Marine and Dive Team, the Charleston County Marine and Dive Team, Charleston County Volunteer Rescue Squad and EMS.