Officials with Yellowstone National Park say after five days of searching, the effort to find Kim Crumbo at Shoshone Lake has transitioned to a recovery mission.
Crews have swept all the trails in the area, searched the entire shoreline by boat and griddled the open water by helicopter. A Facebook post says they did not find Crumbo.
On Friday, crews from the National Park Service's Submerged Research Center will start using sonar equipment to detect clues in the water. Park search crews continue to search for Crumbo by foot and boat, with help from Grand Teton National Park's interagency helicopter.
The post says recovery efforts will continue for the next several days as conditions allow.
Park search and rescue crews found the body of Crumbo's brother, Mark O'Neill, earlier this week along the east shore of Shoshone Lake. The two were on a four-night backcountry trip to the lake.
The incident is still under investigation and officials can't comment further about the investigation specifics. If you have information that could help investigators put together a timeline of events, or if you were in the area of the lake between September 12 through 19, call the National Park Service at 307-344-2428 or email yell_tip@nps.gov.