Federal wildfire authorities issued a new warning today against the use of remote controlled drones they say could interfere with firefighting aircraft and put firefighter lives at risk.

This year, there have been at least three instances of an unmanned drone flying in restricted airspace near a wildfire, the National Interagency Fire Center said Friday.

In July, a private drone was banned from flying over the Sand Fire in Northern California after authorities said it put fire crews in danger.

"Unauthorized UAS [Unmanned Aircraft System] flights could cause serious injury or death to firefighters on the ground. They could also have midair collisions with airtankers, helicopters, and other aircraft engaged in wildfire suppression missions," said NIFC, a federal firefighting organization made up of eight agencies including the U.S. Forest Service and the National Park Service.

Unauthorized drone flights, the agency says, "could lead fire managers to suspend aerial wildfire suppression efforts."