ROBERTSON COUNTY, Tenn. (WKRN) – The Greenbrier Police Department is investigating the “unexplained death” of a 16-year-old boy after he and others reportedly drank racing fuel.

Last week, Logan Stephenson, a student at Greenbrier High School, was found unresponsive inside his Greenbrier home and pronounced dead at the scene.

A second teenager, Logan’s best friend, was taken to Vanderbilt University Medical Center for what police said was an “undisclosed ailment.” News 2 has confirmed the teen has since died. His identity was not immediately released.

“Our hearts are heavy today as we have learned that a second young man has died from the incident last week,” said Sheriff Bill Holt. “We ask that everyone continue to pray for both of these families as they go through this tragic time.”

Authorities say the two cases are related and no foul play is suspected.

They’ve received information both boys were among a select group of teenagers in Greenbrier who may have ingested a racing fuel-based liquid substance last Wednesday, one day prior to Logan being found dead.

Neither deaths have been connected to drinking the racing fuel at this time.

The investigation continues into both teen boys’ deaths. The sheriff’s office is awaiting toxicology results.

Police say if you know someone who may have consumed a similar mixture, the department urges you to seek medical attention at once.

The sheriff’s office is also asking people to refrain from posting or spreading rumors regarding the circumstances as they are “deeply disturbing and harmful to the families that are already going through a tragic time of loss.”

Investigators told News 2 two other students admitted to drinking the mixture but they’re okay.

Logan is survived by his parents, grandparents, and six brothers and sisters.