Video: See the Rescue Effort Following Sunday's Pleasure Boat Accident by Illinois River Dam

Emergency workers continued the search for a missing pleasure boater following a Sunday afternoon accident near the Dresden Lock and Dam.

A married couple, their son and the son’s girlfriend were on a boat near the dam when flotsam struck the craft's motor, according to CBS Chicago.

The father shut off the motor and tried to remove the debris, CBS said it was told by a spokesman from Illinois Department of Natural Resources.

When the father was unable to get the boat's engine going again, a "swift current apparently pulled the boat past the dam, and three people either jumped or fell in the water. The fourth person was able to stay on the boat," CBS said.

Todd Sherman provided video of the search effort.

The search continues for the final missing boater.