A target shooter admitted starting the brushfire that became the massive Sawmill Fire, a newly released Pima County Sheriff’s Department report confirms.

The man, Dennis Dickey, approached a sheriff’s deputy near the scene of the fire’s origin on the day it started near Madera Canyon south of Tucson, April 23, and told him he had been using Tannerite, an explosive powder, and “that was what caused the fire,” the report says.

The deputy, Benjamin Harrison, wrote that Tannerite is easily purchased, can be detonated by a high-velocity rifle round and is commonly used in target shooting. The patented substance has been linked to wildfires in several other Western states, as well.

Dickey also said he was one of the people who reported the fire, says the deputy’s report, released Monday by the Sheriff’s Department in response to a public records request filed May 1.

The sheriff’s report does not mention that Dickey is a Border Patrol agent. The Border Patrol has said one of its agents is being investigated in connection with off-duty recreational shooting that caused the fire.

The fire started on state land, where target shooting is illegal. The Forest Service is investigating but has declined to discuss the case. Heidi Schewel, a Forest Service spokeswoman, said Monday she does “not have answers” to questions about the investigation’s status or when it might be turned over to other law enforcement authorities.

Tucson attorney Sean Chapman said Monday he represents Dickey and that he is cooperating with authorities.

A woman who answered the phone at Dickey’s Green Valley home in early May told a Star reporter, “We already have a lawyer. We’re not allowed to speak to anyone. ... Do not contact us.”

The fire, which sparked on a windy day and spread rapidly, went on to burn about 47,000 acres total on state, federal and private land. It cost $7.3 million to fight, authorities have said.

The manager of the state-owned rangeland where the fire started wrote an email in late April warning that a tougher measure may be needed to make people more aware of the consequences of target shooting on state trust land. The State Land Department released that email to the Star Monday in response to a public records request.

The current ban is “somewhat of a loose regulation,” said Mark Heitlinger, manager of the Santa Rita Experimental Range, which had 5,000 acres burned during the fire.

The first reports of target shooting starting the fire came to authorities shortly after the blaze began along Box Canyon Road a bit east of Madera Canyon, the sheriff’s report said. Sheriff’s Department communications staffers said that one caller was “a female advising the fire was caused by subjects shooting at a metal target resulting in sparks and the fire,” the report said.

The fire started on a privately run cattle ranch that’s part of the 80-square-mile experimental range, an area University of Arizona researchers have managed for many years to research sustainable grazing practices. It was reported to authorities shortly before 11 a.m. on April 23. Numerous callers reported seeing smoke at that time as far away as the Desert Diamond Casino, on West Pima Mine Road and Interstate 19.

Sheriff’s Deputy K.V. Joyce reported that when he arrived at the scene shortly after the blaze began, he was told by Andrew McGibbon, owner of the Santa Rita Ranch, that “the area where the fire started was commonly used by target shooters on State Trust Land in which target shooting was not permitted. He stated that he had told numerous people numerous times to vacate the property because it was located on state trust land and not on Forest Service land.”

McGibbon and his family were evacuated from the ranch at that time, Joyce wrote, because the deputy said he saw the fire start to move rapidly toward the road at McGibbon’s property and he saw the fire was extending higher than the average mesquite tree.

On April 27, four days after the fire started, experimental range manager Heitlinger wrote an email saying, “The Sawmill Fire has evolved into a very severe, dangerous, and costly incident. It was caused by shooting on State Trust Land. This elevates my thought that something stronger than the current policy, for example an actual statute, might help in elevating the awareness and consequences of target shooting” on state land.

In an interview Monday, Heitlinger detailed his concerns, saying that the only mechanism in place today to prevent target shooting on state land comes on a permit that recreational users must buy to occupy state land. It contains various conditions, including one forbidding target shooting, he said. The Land Department has not responded to a question from the Star as to whether Dickey has such a permit.

“There’s nothing else to prevent target shooting other than this restriction on a permit,” Heitlinger said.

“If an enforcement officer finds someone target shooting, what is the enforcement officer going to do? What questions is he going to raise? I’m just raising the questions. I don’t have the answer to it,” Heitlinger said.

There are some signs on the range that list the rules for state land users, and “my recollection is that the target shooting ban is on the signs,” Heitlinger said. He said two of the signs lie within probably a quarter-mile of where the fire started, but “I would have to go out and look to confirm that.

“The range itself is not completely posted. It’s 80 square miles. It’s something we’ve talked about doing, but it’s a huge job,” he said.

Contact reporter Tony Davis at tdavis@tucson.com or 806-7746. On Twitter@tonydavis987

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