EDDYVILLE, Iowa – The search for a missing boater in the Des Moines River stretched into its second day, with no sign of the man, according to Mahaska County Sheriff Russell Van Renterghem.

47-year-old Waylon Straube, of Eddyville, was thrown from a boat along with 50-year-old Roseanne Benda, of Corydon, around 9:50 a.m. Sunday, according to a news release.

It is believed the boat may have struck concrete under the water near 310th Street, which caused the pair to be ejected, Sheriff Van Renterghem told WHO 13’s Katie Kaplan. Benda was located floating in the river by deputies using a drone. The sheriff’s office was then able to connect with nearby fishermen with a boat who were able to navigate to the drone’s location and pull Benda from the water.

Benda was reportedly unharmed.

Multiple law enforcement agencies spent more than 10 hours searching for Straube on Sunday before the effort had to be paused when daylight ran out. The search picked up around 8 a.m. on Monday with multiple boats, many of which were equipped with sonar, said the Sheriff. As of 6 p.m. Tuesday, the search was ongoing.

If Straube is not located by sundown on Tuesday, the search is expected to span into a third day.