CONCOW — Firefighter radio transmissions indicate that a possible “second start” of the Camp Fire was caught on a firewatch camera near Concow Reservoir, about a half-hour after the first flames were reported about five miles northeast near Poe Dam and Pulga.

At 7:04 a.m. Nov. 8, a fire dispatcher rerouted a couple of fire crews to a “possible second fire” on Rim Road, just east of Concow Reservoir. Satellite images indicate that Rim Road crisscrosses underneath several PG&E high-tension lines in that vicinity. There are no obvious radio discussions indicating what may have sparked that second fire, in a review of archived radio chatter.

Minutes later a firefighter described the initial blaze as having grown to about 300 acres with a rapid rate of spread and heading toward Concow Reservoir. Firefighters responding to the second ignition alerted other crews to “two little kids walking the road” along the lower portion of Rim Road, also called Andy Mountain Road, near Jarbo Gap on Highway 70.

On Thursday, the Chico Enterprise-Record reported that security guards had set up a roadblock the day before outside Concow. Later, Cal Fire-Butte County Chief Darren Read confirmed that investigators have identified a “possible second origin” for the fire. He did not release any additional information regarding the second origin point, saying the fire remained under investigation.

Cal Fire spokesman Scott McLean also declined to elaborate Friday.

“Our investigators, Cal Fire, have identified a possible second origin for the Camp Fire,” he said. “The fire remains under investigation, and no further details will be released at this time.”

No cause has been determined for the Camp Fire, according to Cal Fire. In addition to the first radio reports of a downed power line near Poe Dam where the first ignition began, PG&E reported to state regulators that minutes before the fire was reported, a transmission line had a malfunction in the area of the dam.

It’s unclear which firewatch camera possibly captured the second ignition. However in 2014, PG&E announced it funded $2 million to install 28 remote fire sensing cameras on “some of the most important lookout towers” in four counties, including Butte.

Butte County District Attorney Mike Ramsey said Wednesday that PG&E is cooperating with fire investigators, but it was not clear whether the utility’s transmission tower caused the fire.

The District Attorney’s Office was involved “in anticipation that if anything is referred to us in terms of a criminal case, that we’re on top of it right now,” Ramsey said.

The Camp Fire has claimed at least 71 lives and has destroyed more than 9,800 homes. It is the deadliest and most destructive wildfire in state history.

Chico Enterprise-Record staff writers Andre Byik and Dan Reidel contributed to this report.