RALLS COUNTY, MO. -- KHQA-TV has reports that Ralls County Sheriff's Office spent most of Wednesday searching for  missing boater.

Terry Marshall, 60, of Hannibal went missing while mushroom hunting along the Salt River, according to Ralls County Sheriff Gerry Dinwiddie.

Family members and co-workers at the boat launch site off of Cincinnati Road near Center, Mo. said told KHQA that Marshall worked at the Northeast Correctional Center in Bowling Green.

The Missouri Highway Patrol found Marshall's boat on a shore near Hunter Fisherman Access 70 Tuesday afternoon.

His truck was parked at a boat ramp.

Ralls County Sheriff Gerry Dinwiddie told KHQA that three sonar boats and two K-9's were brought in to search the river Wednesday.

He said the Salt River, which connects to the Mark Twain Lake, was lowered one foot through a nearby dam to help with the search and that Thursday it will be lowered another four feet.

"Obviously we're looking for a good outcome here," MHP spokesman Sgt. Brent Bernhardt said. "When you're looking for a missing person, you're looking not only in the water, but along the bank, in the event that the subject is injured, maybe has gotten lost. So we're hoping for a good outcome."

Sheriff Dinwiddie said the search was continuing today