Officials with the Los Angeles County Sheriff's Department said the boy went into a men's bathroom at Rio Hondo Park about 2:30 p.m. while his mother waited in the car. The boy was then allegedly pulled into a stall by the suspect and was raped.
A witness said the man calmly walked the boy out of the bathroom to the car where his mother waited and said the boy was crying for her.
"The little boy was screaming and he said, 'Here's your mother.' He goes, 'Your son is crying for you,' and the little boy was looking at him frightened saying, 'No, no,'" witness Gia Singerman said. "The mother said what happened, what's going on? And the man lightly just walked away really calmly and the little boy had told his mother that he was raped."
As the mother started screaming for help at the crowded park, the suspect fled the scene.
Detectives said the suspect drove across part of the park to get away. He was driving a newer model white minivan similar to a Dodger Caravan with a California license plate that started with "6J."
The boy was recovering at the hospital. The extent of his injuries were not immediately known.
The suspect was described as Caucasian, about 30 years old, 6 foot 1, 200 pounds with blond hair and blue eyes. He had tattoos on his neck and on at least one arm. He had a Mexican flag bandana on his head.
Anyone with information is urged to call the sheriff's special victims unit at (877) 710-5273.