From the time of his death more than 19 months ago, the parents of a Valdosta teen whose lifeless body was found inside an upright gym mat have insisted their son’s death was no accident.

Tuesday, they filed a wrongful death lawsuit against Lowndes High School officials, accusing them of failing to protect their son from repeated harassment by a classmate.

Kendrick Johnson, 17, was “violently assaulted, severely injured, suffered great physical pain and mental anguish, and subjected to insult and loss of life, all of which took place at the hands of one or more students while on (school) property.”

While the suit does not name the student, representatives for the family have repeatedly pointed the finger at the son of a FBI agent and his older brother even though they had alibis at the time of Johnson’s death.

The complaint —which follows a suit filed in May alleging negligence by school officials — refers to a fight between Johnson and the classmate as they traveled to a football game. The student “had a history of provoking and attacking” Johnson at school, the suit alleges.

Lowndes Sheriff’s Lt. Stryde Jones said the students implicated in the lawsuit were never suspects.

“You can’t just accuse somebody with no evidence,” former Lowndes-Valdosta NAACP President Leigh Touchton said.

Warren Turner, attorney for the Lowndes County School System, said the school had not been served with either lawsuit and declined comment.

Lowndes County Sheriff’s investigators concluded that Johnson’s death was accidental. Their theory: Johnson reached into the mat from above to retrieve his gym shoes, which he shared with a friend and stored underneath the mats, and got stuck.

Typically, he would tilt the mat to retrieve the sneakers but investigators believe Johnson was running late for a weight training class and, in his haste, reached from above instead of removing the surrounding mats to the side.

An autopsy identified the cause of death as suffocation.

Johnson’s parents say school officials conspired with law enforcement to cover up their son’s murder.

“It’s lie after lie after lie that we’ve been told, and we won’t stand for it,” Kenneth Johnson said on the one-year anniversary of his son’s death.

Race and class have been at the heart of the cover-up, they claim, and the incident has attracted national headlines. In Valdosta, the divisions aren’t that clear, as two of the area’s most prominent civil rights activists broke with the family and supported the official version of Johnson’s death.

“You’ve got too many people involved for me to believe there could be a cover-up,” the Rev. Floyd Rose, longtime president of the local branch of the Southern Christian Leadership Conference, told The Atlanta Journal-Constitution earlier this year.

Still, concerns over how the the investigation was handled led Michael Moore, U.S. Attorney for the Middle District of Georgia, to launch a review of the case last October. He said he would not comment until concluding his probe, which is expected soon.