Omar Villafranca, NBCDFW.com
Police hope surveillance footage can help identify the teenager who beat and sexually assaulted a woman Thursday morning.
Police hope newly released surveillance video can help identify a teenager who assaulted and raped an employee at a Dallas public library.
The teenager attacked the cleaning woman at the Kleberg Rylie Branch Library on Edd Road just before 9 a.m. Thursday.
Police said the teenager followed the victim when she went outside to her car for something she had forgotten. He beat and sexually assaulted her outside the building, police said.
The surveillance video shows him leaving the building about three minutes later.
"Although it only lasted three minutes, it will forever change the life of the individual that's involved," Deputy Chief Craig Miller said.
On the video, he covers his face as he walks down the hallway.
"You can see from his cowardly act that he's hiding his face, possibly knowing that there is a camera present," he said.
The surveillance video doesn't show who the teenager was following.
"It's obviously a stranger-on-stranger crime," Miller said.
Women who work and live near the library said the incident has made them uneasy.
"Being a female, I mean I work right down the street," Angela Fisher said. "It was just shocking that it happened right in this neighborhood. You just have to be careful who you talk to."
Investigators said they hope someone recognizes something from the surveillance video.
"This is an incident that preys on all of us," Miller said.