12/26/2014 09:09 am ET Updated Feb 25, 2015

Wisconsin Nonprofit to Provide High-Tech Help in Search for Two People Missing Under River Ice in Remote Alaska

The Alaska State Troopers and Bethel Search and Rescue are getting help in their search for two people missing since Dec. 12 on the Kuskokwim River.

A Wisconsin man who started a nonprofit to safely recover submerged bodies will be bringing high-resolution side-scanning sonar equipment to the search on Dec. 26.

Meanwhile, searchers from Bethel, Kwethluk, Akiak, Akiachak, Atmautluak, Napakiak and Napaskiak, along with the Alaska State Troopers, continue to drag an open, ice-free lead and under river ice where the body of one of the missing, Ralph "Jimmy" Demantle, 51, was recovered on Dec. 14.

Bethel Search and Rescue spokesperson Perry Barr, a retired state trooper, said crews made good progress Christmas Eve dragging over new spots on the river and re-examining spots previously checked by more than 35 volunteers.

"We are very hopeful that this apparatus that he is bringing with him is going to be beneficial for not only this search but also for searches in the future that we may have, unfortunately," Barr said late Wednesday.