LIVERMORE (CBS SF) — A Livermore woman was sexually assaulted and injured on the Arroyo Trail Tuesday, according to police.

The 29-year-old woman was walking in the area of Arroyo Trail and Arroyo Road around 6 p.m. on Tuesday when she was approached and grabbed from behind by a male suspect and sexually assaulted.

The suspect then fled the area.

He is described as a white male adult in his early to mid 30s, with dark eyebrows and features. He was between 5 feet 10 inches and 6 feet tall and weighed between 180 and 190 pounds, and was wearing a dark hooded long sweatshirt and dark colored baggy sweatpants. He was described as being unshaven, dirty and “scruffy” in appearance, according to police.

The victim is being treated for her injuries, police said.

The attack is under investigation and police have said they will provide extra patrols in the area.

Police said they have responded to at least three sexual assault calls on the Arroyo Trail in the south Livermore area in the past three years, all of which involved sexual battery. It is not known whether any of those cases are related to the current assault, police said today.

Police urged residents walking in the area to remain alert and aware of what is happening around them, stay out of secluded and poorly lit areas and avoid wearing headphones that cover both ears.

People using the trail found the news very concerning.

“It makes me want to get a concealed weapons permit, so that if it were to be me, I could take care of it, since the police won’t,” one hiker said.

Whenever possible, residents should walk with another person, and carry a cell phone programmed with the direct number for Livermore police dispatch, (925) 371-4987. Any suspicious behavior or persons should be reported to the police.

Anyone who witnessed Tuesday’s assault should call police at (925) 371-4777.

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