It happened Tuesday around 3 p.m. at Pico Park off Beverly Boulevard.
The Los Angeles County Sheriff's Department said the suspect allegedly grabbed the girl's arm and pulled her as she walked through the park.
A Good Samaritan intervened and threatened to call police, authorities said.
That's when the suspect let her go, but not before authorities said he allegedly reached for a child that was with the Good Samaritan, but was unsuccessful. He ultimately took off running and remains on the run.
Driver sees man dragging woman in attempted kidnapping, scares him away; hero, victim reunite
Driver sees man dragging woman in attempted kidnapping, scares him away; hero, victim reunite
The suspect is being described by authorities as a Hispanic man between 30 and 35 years old.
He's reportedly 6 feet tall and weighs 200 pounds, according to authorities.
The sheriff's department said he has "salt and pepper shaggy hair" and was last seen wearing a black sweatshirt with black pants and tattered shoes.
Anyone with information is encouraged to contact the Pico Rivera Sheriff's Station at 562-949-2421.