REDWOOD CITY (CBS SF) -- A woman was attacked at knifepoint in a garage at a Redwood City high school on Monday evening, a police sergeant said.

Officers responded to a report of an assault at Summit Preparatory Charter High School at 890 Broadway St. at about 6:05 p.m., Redwood City police Sgt. Sean Hart said.

The victim—an employee at the school—was walking to her car in an underground parking garage when she was approached by a student, Hart said.

The student was later identified as David Velasquez, 19, of Redwood City, police said.

Velasquez was allegedly carrying a knife when he grabbed the victim and forced her toward her vehicle, according to police.

The two struggled, during which the victim was pushed to the ground, Hart said.

A witness entered the garage, saw what was happening and yelled at Velasquez, who ran away, police said.

The woman suffered minor injuries in the attack, which investigators believe was intended to be a sexual assault, police said.

Police tracked down Velasquez and arrested him on suspicion of kidnapping, assault with intent to rape, false imprisonment and making terrorist threats.

Anyone with information regarding the incident is asked to contact Redwood City police at (650) 780-7100. Those wishing to remain anonymous can call the tip line at (650) 780-7110.

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