District Attorney Michael Knowles said in a statement federal investigators have determined how the fire started and who started it, the Los Angeles Times reported.
"Federal prosecutors have privately declared an intention to prosecute," Knowles said in a statement.
A spokeswoman for the U.S. Attorney's Office for the Eastern District of California declined to comment, the newspaper said.
The fire -- the third-largest in California history -- broke out Aug. 17. It destroyed 11 homes and burned 402 square miles in Yosemite and Stanislaus national forests.
Tuolumne County officials said in September the fire started when the hunter evidently lost control of a campfire.