(CNN) -- A police bomb squad detonated a suspicious device Friday afternoon in an alleyway in southwest Detroit, according to police spokesman Phillip Cook.
The device was constructed using a "plastic bottle with some type of battery attached to it," he said.
Police are investigating at least one other device found at the scene, Cook added.
The incident follows one on February 26 in which a package containing "explosive components" was left unattended for weeks in a Detroit federal building.
That package was placed in a lost-and-found room before being reported to police, resulting in the suspension of a building security guard
Police say the devices found Friday were not located near a federal building.