The woman told police that she was walking from the Broadway Plaza area around 5:30 p.m. when a man crept up behind her and assaulted her. From his actions and comments, it was clear he intended to sexually assault her, she said.
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For an unknown reason, the man suddenly fled, running northbound on South Broadway, according to police. The woman was treated for injuries not considered to be life-threatening.
Walnut Creek police and officers from the East Bay Regional Park District searched the area, but couldn't find the suspect, police said. East Bay Regional Parks police confirmed Saturday that they had arrested the suspect.
Anyone with any information is urged to contact the East Bay Regional Park District Police Department's tip line at (510) 690-6521.