Helicopter rescue?

On Saturday, June 4, our hiking party was having lunch around noon above Nevada Fall. We saw a red helicopter swing very fast and low into the Merced river canyon between Nevada and Vernal Fall, hover a half minute over the river as if looking for someone who had fallen in, and then fly away. Does anyone know if there was a hiker who had tragically fallen into the river along the Mist Trail? With the heavy run-off now, the news can't be good.

There's nothing in the news so it was probably just for construction.