The 42-year-old suspect was taken to the public safety building and interviewed by police, who arrested him on suspicion of felony child kidnapping. Alcohol or drugs may have been a factor in the suspect's behavior, McGowan said.
An hour after the attempted kidnapping a fist fight turned especially dangerous when a man with a knife stabbed a man in the stomach and slashed another in the side.
The girlfriend of one of the victims identified the slasher to police. The suspect remains at large, but gang detectives recognized the man's name and are searching for him, said Salt Lake police Detective Veronica Montoya.
The 18-year-old man stabbed in the stomach was taken to the hospital where he underwent surgery Thursday night. The other 18-year-man who was slashed in the side was treated on scene and declined to be taken to the hospital.
Despite the incidents, the Pioneer Day celebrations in Liberty Park were calm compared with previous years, said city spokesman Art Raymond.
"Any time you have a public gathering with thousands of people, inevitably there's going to be some element of public disorder. That's why we staff events the way we do," Raymond said. "The law enforcement presence proved to do what it is supposed to do, which is to respond quickly to these incidents."
The Liberty Park celebration included bouncy houses for children, plenty of food booths and the annual Native American celebration.