CLAYTON, Mo. -- A 19-year-old from Forsyth County who allegedly stole a tip jar from a suburban St. Louis Starbucks and ran over a Good Samaritan trying to stop the crime faces criminal charges.

Aaron Poisson of 1220 Old Home Place Court, Cumming, was charged Friday in St. Louis County with involuntary manslaughter, leaving the scene of an accident and theft in the hit-and-run death on Monday. The first two counts were felonies, the third a misdemeanor.

St. Louis County Prosecuting Attorney Robert McCulloch said murder charges were not filed because all evidence indicates Poisson did not intend to kill Roger Kreutz, 54, when he allegedly ran over him. Kreutz had run outside of the Starbucks, pursuing Poisson after he saw him steal the tip jar.

"It just kind of indicates all the horrible consequences that can come from a relatively minor offense," McCulloch said.

Poisson graduated from South Forsyth High School in 2007. He was a starting pitcher for the school's baseball team in 2006, but did not return to the mound his senior year.

McCulloch said Poisson and a young female companion were traveling through the St. Louis area Monday when the accident happened.

The companion's name has not be released and no charges will be filed against her, McCulloch said. He said the couple didn't appear to be hiding from the law this week as a massive manhunt was mounted to locate them.

"They were still in the area and not actively hiding from authorities as far as we can tell," McCulloch said.

Poisson's father, Gary Poisson, told the St. Louis Post-Dispatch that Aaron Poisson and his girlfriend of three months have been on a cross-country road trip the past several weeks.

Gary Poisson told the St. Louis newspaper that the couple was arrested in February for shoplifting in Cincinnati.

Gary Poisson said he and his wife were disappointed when the two started seeing each other, claiming that his son was polite and "everything changed" after he got involved with the girl.

Poisson was arrested Thursday at a St. Louis residence, said Crestwood Police Chief Michael Paillou. Poisson was in town searching for a job and planned to move to the St. Louis area, Paillou said.

Former South Forsyth High School classmate Steven Counts said he knew Poisson from math class. "He was kind of a troublemaker," he said. "He talked back to the teacher."

Poisson is being held at the St. Louis County Justice Center in Clayton on $50,000 bond. McCulloch said he likely would be arraigned Monday morning. Poisson does not yet have an attorney in the case, according to court filings.

Paillou declined to discuss the case further because it is now in prosecutors' hands. He said the arrest means Crestwood residents can move past the incident.

"I hope we did our part for Roger's family," Paillou said.

Kreutz was a regular patron at the Starbucks and well-liked by employees there. According to video surveillance of the incident, he didn't hesitate to chase Poisson out the door after he saw the tip money had been stolen. Police say Poisson made off with about $5.

The Forsyth County News and the St. Louis Post-Dispatch contributed this report.