An anonymous email claiming a former classmate of Kendrick Johnson had confessed to killing him was investigated and determined not to be credible, the Lowndes County Sheriff’s Office said Thursday.

Sheriff’s Lt. Stryde Jones said the unidentified sender of the Jan. 27 email reported a friend had overheard a person say that her boyfriend had murdered Johnson, and that authorities should know that information.

Johnson, 17, was found lifeless in a rolled-up athletic mat in the Lowndes High School’s old gym 14 months ago. The sheriff’s office and the Georgia Bureau of Investigation ruled the death a freak accident that occurred when Johnson became trapped upside down for several hours in the vertical mat while trying to retrieve a pair of athletic shoes. Johnson’s parents, however, contend he was the victim of foul play, possibly murder. A federal grand jury, the U.S. Attorney’s Office in Macon and the Federal Bureau of Investigation are reviewing the case.

Jones said sheriff’s investigators interviewed two of the four individuals mentioned in the anonymous email and determined it was unlikely a confession had occurred. Jones said among other details that didn’t add up was the determination that none of the individuals had attended the party at which the confession supposedly was overheard.

The email investigation included identifying the anonymous email author through a district attorney’s subpoena to the sender’s Internet service provider, Mediacom Communications company. Authorities then interviewed the individual, along with three teenage friends.

“We identified the (email) source as a juvenile who attends Lowndes High School,” said Jones. “Everything the kids heard was rumor and speculation on the part of other people. We found no credible information to support the statements made in the email.”

Jones said the email sender did not claim to have witnessed anyone confessing to killing Johnson or having knowledge of possible foul play in his death.

“We received a tip, and we immediately started

interviewing,” said Jones. “We didn’t find anything at that point to determine that the information was credible.”

Jones said it was determined the anonymous email was sent in “good faith” and that the author, who is a juvenile, will not face charges of making a false statement to law enforcement.

“We did not feel that the sender had any ill intent and was just passing on what had been heard,” said Jones.

The sheriff’s office continues investigating the tip.

The statement by the sheriff’s office was made in response to a CNN report Wednesday reporting it had obtained the email and a subpoena through a public records request, and local officials were investigating a possible confession.

Johnson’s strange death has triggered several Internet rumors and widespread speculation as to possible foul play since it occurred more than a year ago. At one point, a $10,000 reward was offered through the Rev. Floyd Rose, a longtime local civil rights activist, for evidence that would contradict the official finding of an accidental death. Rose withdrew the offer when nothing turned up after several months.