Anna Kepner's mysterious death aboard a Carnival cruise ship was a homicide by "mechanical asphyxiation," according to a new report.

The 18-year-old was found dead aboard the Carnival Horizon on Nov. 7, around 11:15 a.m.

"Mechanical asphyxia just means there is something external to the body that hinders her breathing — her chest or belly can't expand," said Dr. Priya Banerjee, a board-certified forensic pathologist. 

The Miami-Dade Medical Examiner's Office declined to comment, citing the ongoing investigation.

The teen's death was ruled a homicide, and she was "mechanically asphyxiated by other person(s)", found dead under the bed in her cabin, wrapped in a blanket and covered in life jackets in a room she shared with the stepbrother.

Both of his parents and their attorneys have not responded to multiple requests for comment from Fox News Digital.

Kepner was a high school varsity cheerleader who planned to join the Navy after graduation and ultimately wanted to become a K-9 police officer.