A social media post by a 17-year-old in which he claims to have killed his friend over “jealousy” was among the evidence police used to book him Thursday with a count of second-degree murder.

According to court documents, Michael Dixon told investigators the shooting that killed 15-year-old Chance Smith on Sept. 18 was an accident. But he later admitted he lied during his first conversation with detectives, according to a warrant for his arrest.

Dixon’s initial story was that he put a handgun on a chair next to Smith as the two sat outside of Smith’s Algiers home in the 3900 block of Sullen Place. Dixon told police that the gun went off as he, Smith and another friend watched a video online.

Dixon told detectives he saw Smith fall to the ground and tried to perform CPR on him. Smith died a short time later at University Medical Center.

But detectives later found two Instagram accounts that they believe belong to Dixon.

Smith’s brother told police that Dixon sent him a message on one account and apologized for the shooting, saying it was an accident. He wrote in another post, “I killed my 15 year old friend over jealousy,” according to the warrant. It was not clear from the warrant what Dixon was apparently jealous about.

Also helping to unravel Dixon’s story, detectives wrote, were Smith’s autopsy results.

“The trajectory of the bullet indicated the weapon was raised to the chest region of the victim,” homicide Detective Thaddeus Williams wrote in his warrant, “which implied the gun was raised and not on a chair at the time of the shooting.”

Williams also wrote that Dixon tested positive for gunshot residue. Dixon remained jailed Friday. His bond was set at $200,000.

Smith’s classmates held a peace rally in his honor Friday evening at Eleanor McMain Secondary School where he was a freshman.

“The only way that we’re going overcome gun violence in the city of New Orleans is that collectively we really do have to rise up against it,” Mayor LaToya Cantrell said.

Smith, meanwhile, was remembered as a quiet kid.

“Chance Smith was not a gangster. He was not bad. He was just a little game head,” Cortell Smith, Chance’s older brother, said. “Ain’t no hurt worse than losing a little brother. I have to go home every day and just not to see him. … All we have is memories of him.”

New Orleans Advocate reporter Ramon Antonio Vargas contributed to this report.