ST. CLOUD, Minn. - A St. Cloud man faces the possibility of a 40-year prison sentence after a chance encounter and a single punch led to the filing of murder charges Tuesday.

A criminal complaint details the charges of second degree unintentional murder against 21-year-old Travis Allen Johnson. Prosecutors maintain Johnson was in a group that made contact with another group that included 22-year-old Anthony Quinn Shriver of Waconia shortly after 2:30 a.m. Witnesses say an exchange of words ended with Johnson punching the victim in the side of the head as he tried to walk away, knocking Silver unconscious.

According to court papers the whole incident was caught on surveillance camera. And that the camera showed Shriver tried to walk away, when the suspect took a swing and hit him on the side of the head.

Police were called, the victim's friends provided a description of his assailant, Johnson was identified and detained by police. Shriver told officers he hit his head and remembered nothing about the incident, but declined medical attention.

More than nine hours later police were dispatched to a home on the 2200 block of 10th Avenue South in St. Cloud and found Anthony Shriver unresponsive. Despite life saving measures, he was pronounced dead at 1:10 p.m.

"We asked and he appeared all right. He said his head hurt. But he felt like he was going to be fine. And he went on with the friends he was with," said Assistant Chief Jeff Oxton with St. Cloud Police.

Shriver's family say the 22-year-old took great pride in working out and dressing sharp. He loved snowboarding and skateboarding... and leaves behind a girlfriend of 5 years.

An autopsy performed on Shriver by the Ramsey County Medical Examiner indicates he died of "traumatic head injuries due to physical assault."

"I think it just shows that what some people take as maybe not a very significant act can change in a second and affect multiple people's lives," Oxton said.

During a court appearance Tuesday a judge approved bail of $1 million without conditions, or $250,000 if he abstains from alcohol, agrees to stay in Minnesota without prior approval, and turns in his passport.

Johnson's next appearance in Stearns County District Court is August 21.

The Shriver family has a GoFundMe page set up to help with funeral costs.