Though the official cause of death has not been released, Parris said witness statements indicate that an error made by either the firefighter or the crew led to the fatal fall.
Marovich had completed two years as an apprentice with the U.S. Forest Service at the Modoc National Forest.
At the time of the accident, he was training with the Chester Helitack Crew from the Lassen National Forest, which had been recently dispatched to the 6,300-acre Backbone fire burning near Willow Creek in Humboldt County.
The accident comes less than a week after two pilots walked away from a helicopter crash while fighting the same fire. In that case, the helicopter flipped on its side while refilling its water tanks between runs.