Crews from at least 20 agencies have been helping Buffalo Police look for one of its divers who went missing during a training exercise on the Niagara River this past Friday October 13, 2017.
Craig Lehner, 34, was a member of the Buffalo Police Underwater Recovery Team.
Over the course of four days, crews from both sides of the border have been trying to find Lehner with helicopters, robotic cameras, divers and sophisticated sonar equipment.
Buffalo Police were hoping to finally find their "lost brother" but conditions on the Niagara River were not favorable with visibility near zero - thanks to a strong storm on Sunday that churned up Lake Erie and the river.
According to Buffalo Police Spokesperson Lt. Jeff Rinaldo, crews received additional assistance from the U.S. Army Corp of Engineers which provided two boats with advanced side-sonar equipment.
The U.S. Coast Guard also did an analysis of the water currents at the time of Lehner's disappearance to try and pinpoint where the fast moving water may have carried him.
Adding to the complications is a large debris field in the Niagara River that, combined with swift waters, is making it challenging for sonar because of reflections and false readings.
7 Eyewitness News Reporter Ed Reilly has the latest on the search efforts.