(CNN) Eleven hours before she shot up YouTube headquarters and then killed herself, Nasim Najafi Aghdam chatted with police.

It was 1:40 a.m. Tuesday, and Aghdam was hundreds of miles away from home. Police found her car overnight at a Mountain View parking lot, about 30 miles southeast of YouTube headquarters.

A quick check of her license plate revealed the owner had been reported missing from the San Diego area.

"We contacted the woman inside the vehicle, who was asleep, to check on her and to determine if she was the same person who had been reported missing," Mountain View police said.

Nasim Najafi Aghdam shot and wounded three people before killing herself, police say.

"At no point during our roughly 20 minute interaction with her did she mention anything about YouTube, if she was upset with them, or that she had planned to harm herself or others ... she was calm and cooperative."

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