OAKLAND (KRON) -- Oakland police are trying to figure out who built and planted a replica of a pipe bomb at the downtown Salvation Army facility.

An employee at the charitable organization says he came across a cooler Thursday morning.  When he looked inside he saw wires, foam, and other things that made the device appear to be a bomb.  

That worker called police who asked for the Alameda County Bomb Squad.  The Salvation Army was evacuated and people in nearby businesses on 7th street were told to stay inside.

The bomb squad sent in a robot to get a better view of the device and eventually to detonate it.

"We went down with the counter-charge to open the device and find out what was inside," Alameda County Sheriff's dept spokesman Sgt. J.D. Nelson said.  "What we found inside is what I would consider to be a very well-made hoax device. It was not explosive in nature.  It was a series of wires wrapped around a steel bar and certainly made to look like a pipe bomb that could have been electronically detonated."

It's unclear how the cooler with the fake device ended up at the Salvation Army facility.  If you know anything about this crime, contact Oakland Police or the Alameda County Sheriff's Department.

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