An autopsy is pending for a Butte La Rose fisherman found in the Atchafalaya River on Tuesday morning.

Authorities believe William K. Seal, 56, fell overboard while fishing in the river in St. Martin Parish, said Adam Einck, spokesman for the Louisiana Department of Wildlife and Fisheries, which is investigating the case.

“His body was found without a life jacket. We don’t know what happened that didn’t enable him to get back in the vessel. We do feel he went overboard at some point,” Einck said on Tuesday.

A barge operator found Seal’s body around 7:30 a.m. on Tuesday, two days after a tugboat operator found Seal’s 15-foot, unmanned boat floating in the river, Einck said.

Authorities began searching for him on Sunday after he did not return to the Butte La Rose boat launch on Saturday evening.