CHICAGO (CBS)–Police tape, flashing lights and dozens of law enforcement officers surrounded the Aurora Acorn Woods apartment building 45-year-old gunman Gary Martin called home.

The bomb squad searched his place Friday, leaving nothing unturned.

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His neighbors, looking out their windows, connected the dots.

Gary Martin was identified as the man who shot five people at an Aurora workplace on Friday. (Facebook)

Jennifer White said she realized what was going on with Martin when she saw investigators surrounding his car.

“He seemed perfectly fine. I’ve seen him out there with his drones. He seemed perfectly fine,” White said.

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People described Martin as a loner.

“He always kept to himself,” White said.

Neighbors were only familiar with him because of the time he spent outside, flying drones or working on his car.

“He would wave at us or stare at us. Kinda creepy,” White said.

His LinkedIn profile identifies him as a large valve assembler at the plant.

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“He didn’t really have that much,” White said.