Riley Strain's tragic cause of death revealed amid autopsy report being published

Riley Strain's cause of death has been revealed after the publication of his autopsy report.

Police launched a search for Riley after he was last seen leaving Luke's 32 Bridge Food + Drink in downtown Nashville on 8 March.

The 22-year-old University of Missouri student had been visiting Nashville and went to a bar with some of his pals.

Luke Bryan's bar said in a statement said that Riley had been served 'one alcoholic drink and two waters' at the bar before he was escorted out by security at around 9.35pm local time.

The bar claimed the student was asked to leave based on its 'conduct standards'.

Strain told his friends he would go back to the hotel where he was staying, but in an interview with WSMV, his stepfather, Chris Whiteid, said he never made it back to where they were staying.

Two weeks after he was last seen, on 22 March, police confirmed the tragic news that Riley's body had been found in a river.

"BREAKING: The body of Riley Strain was recovered from the Cumberland River in West Nashville this morning, approximately 8 miles from downtown," the department wrote.

Riley Strain left the bar in Nashville by himself. (Metropolitan Nashville Police Department)

It added that there was no indication of foul play, though an autopsy was to take place.

Well, nearly three months later, that autopsy has now been concluded.

NewsChannel Nashville reports that Riley died from 'alcohol poisoning and drowning'.

The student's blood level was .228, which is three times the legal limit.

The autopsy also determined Riley had traces of Delta 9, which is a form of THC, albeit legal in the state of Tennessee, and is not hard to get your hands on.

Riley's death was deemed as accidental by the report.

Prior to his disappearance, Riley was caught on security footage appearing to sway as he walked through the streets after leaving the bar.

He appeared to stumble and even fall over at one point.

Riley was last seen on video around 9:52pm local time, when he spoke briefly with an officer who was responding to a vehicle burglary on a sidewalk adjacent to the Cumberland River on Gay Street.

Riley's death has been deemed as accidental. (Metropolitan Nashville Police Department)

The officer asked Riley how he was doing, to which he replied: "I'm good, how are you?"

News of the autopsy comes just days after his parents walked on stage at the University of Missouri and accepted Riley's diploma from the Mizzou College of Arts and Science.

Stepfather Chris thanked the entire Nashville community for their help in trying to find Riley.

"To the people of Nashville, I can't thank you enough for the support, the love, the encouragement that you've shown myself and my wife," he said.

"It's been an emotional rollercoaster. We're quite thankful for everything that you've done for our family. The grace that you've given us, it means a lot, more than you'll ever know."