A 17-year-old boy was arrested this week in connection with several homemade explosive devices that had been found on the playground of a Waseca elementary school in March. One device was found in a stuffed animal at Hartley Elementary School, and had already been detonated. A second device was detonated by the bomb squad, and a third failed to ignite. The 17-year-old was arrested after authorities searched a home and storage facility in Waseca. Officials say that the teen was apparently plotting to kill his family, create a diversion to get first responders out of the area of the school, and then kill as many as possible at the school before killing himself when confronted by police. More than five handguns and assault rifles were allegedly found in the teen’s bedroom as well, along with explosive devices and ammunition. More improvised bombs and chemicals were apparently found in the storage locker also. The boy is facing felony charges, and is expected to be in court today (THU).