Rescue crews are stepping up their efforts to find a person who is presumed to have drowned in the North Platte River in Casper.

The Natrona County Sheriff's Office has brought in its air-boat, in order to break through areas of ice and help crews find the body of a woman who went under the ice, in middle-January.

Detective Wes Gudahl with the Casper Police Department says crews have not given up the search, but now there's more equipment available for them to use.

"The airboat is now available for us, and we can get out into the water and work some of those channels and things and it's a missing person, and we want to be able to locate who that is and recover who that is and be able to get them to their loved one."

Detective Gudahl says crews are focusing their search on the river between North Center Street and Bryan Stock Trail.

The suspected body is believed to be that of 36-year old Bobbie Stringham, but rescue crews will not confirm that until the body is found.