Montague County Sheriff Paul Cunningham spoke Tuesday about the investigation into the death of Denton Guyer High School student Nathan Maki.
Maki's body was found in a pickup truck that was parked in a field in Bowie on Saturday, where he and 17-year-old Michael Underwood were camping out for the night before going dove hunting the next morning, Cunningham said.
At some point, a rifle held by Underwood discharged and a bullet struck Maki in the head, Cunningham said.
When officers arrived they said Underwood was emotional and visibly upset. Cunningham said there is no evidence the shooting was intentional and he reiterated that it appears to have been a tragic accident.
Underwood was arrested at the scene for consumption of alcohol by a minor. He posted bond and was released.
Cunningham said there were two female witnesses at the camp site, ages 16 and 19, who left the scene after the shooting, who have been interviewed in the case. Cunningham said he did not know if they consumed any alcohol at the camp site and that investigators would likely be talking with them more as the investigation continued.
Officials said whether Underwood faces any charges, which may include deadly conduct or criminal neglect, will be left up to the grand jury.
Maki will be laid to rest Thursday at 11 a.m. at Cross Timbers Church in Argyle. Following that, the Guyer football team, of which Maki was a member, plans to honor the teen's family with a jersey presentation and a video montage during Thursday night's game.
At the high school Tuesday, many students wore blue in memory of Maki while others painted their cars and trucks with his No. 33 jersey number. Some also met with grief counselors in a safe room, talked about their loss and made blue ribbons in his memory.
The booster club has set up an account at Northstar Bank for anyone who wants to make a donaton to Maki's family.
NBC 5's Eric King, Jeff Smith and Kevin Cokely contributed to this report.