DENVER -- A 28-year-old mother who reported her son missing after he didn't show up at the amusement park where she dropped him off earlier in the day faces up to a year in jail and a $1,000 fine for violating a municipal code, Denver police said.

Charlotte Nadine Chavez dropped her 11-year-old son off at Six Flags Elitch Gardens Saturday around 7:30 p.m. so he could meet with some friends. But when she returned at 10 p.m., she was unable to find him, police said.

She waited for nearly two hours before she went home and called Denver police to report her son missing.

The next day, an off-duty officer working at Six Flags recognized the boy in the park and notified police. The boy and his mother were reunited safely.

Apparently, the boy went to a friend's house Saturday night and the friend's grandmother returned him to the amusement park the next afternoon, police said.

Chavez faces the charge of wrongs to minors, which carries a penalty of up to one year in jail and up to a $999.99 fine. The law was designed to protect children from abandonment, city officials said. The charge is similar to a ticket and is handled by the city attorney's office.

"It is important for parents to realize that they must be responsible for their children at all times and not feel that they can just drop off their kids off at such a young age with no adult supervision," said police spokesman Sonny Jackson.

The investigation revealed that Saturday's incident was not an isolated event. Chavez had dropped her son off numerous times before with no adult supervision, police said.

Detective Virginia Lopez said she didn't think police had ever charged anybody under the code.

"The mother needed to be given a wake up call that you can't always dismiss adult supervision," Lopez said.

City Attorney Cole Finegan said the law does not specify at what age it would be appropriate to leave a child unsupervised. The municipal code covers minors under the age of 18.

"It's a policy to ensure that you don't have people abandoning their children or placing them in danger and that there is some accountability,' Finegan said.