The mother of college student Riley Strain, who vanished during a trip with his frat brothers in early March and was later found dead in a Nashville river, said she is skeptical about his death being ruled "accidental."

Strain's mom, Michelle Whiteid, said on the night he disappeared, her son texted her while at Luke's 32 Bridge, mentioning his rum and coke "didn't taste good," according to NewsNation.

"It tastes like barbeque," Whiteid recalled the 22-year-old University of Missouri student saying.

"I go, 'Well, that sounds awful," she told the outlet. "He said, 'Well, it sounds good, but it's not.'"

"Maybe there was something in it that shouldn't have been," Whiteid speculated.

Strain was thrown out of the bar after one drink, and his frat brothers never saw him again.

His body was later found in the Cumberland River March 22. His pants, wallet, and cowboy boots were missing.

A preliminary autopsy report found that Strain died of accidental causes, however Whiteid disagrees.

The family ordered a second, private autopsy after it was found Strain showed no signs of water in his lungs, which is typically expected in accidental drowning incidents.

They are also working to acquire more surveillance footage the night of Strain's disappearance.

The investigation continues.