A federal jury has found a Kansas veteran guilty of unlawfully having explosive materials.

The U.S. attorney’s office said Thursday that Alfred Dutton, of Eureka, was convicted on one count of possession of an unregistered destructive device.  The 67-year-old veteran of both the U.S. Army and U.S. Marines is accused of having grenades and other parts to make destructive devices.

Prosecutors told jurors at his trial in Wichita that Dutton added chemicals to gunpowder to increase the explosive power of the grenades he was making.

His defense attorney portrayed his client as a tinkerer who was experimenting with making fireworks and was working on creating a mock grenade that he planned to sell on eBay.

Sentencing will be set at a later date.