SOUTH PASADENA (CBS)  — Authorities say a 19-year-old man is in custody on suspicion of trying to rape a woman walking alone on a trail through Arroyo Park in South Pasadena.

Jason Daniel Barrios of Los Angeles was being held in lieu of $100,000 bail at the Pasadena jail, according to South Pasadena Police Department spokesman Joseph Payne.

A witness heard the woman screaming for help about 12:40 p.m. Monday and went to assist her. When the witness arrived, the suspect took off, Payne said.

The witness chased the suspect on foot before losing sight of him in the heavy brush along the Arroyo Seco near Stoney Drive and Lohman Lane, he said.

The witness reported the attack to South Pasadena police, who launched an extensive search and eventually found the suspect in the arroyo. The witness identified him, as did the victim, Payne said, adding that the woman was uninjured but her clothing was torn.

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