Matt Tucker, a Springfield firefighter, said he was fishing for bass Tuesday morning in Fellows Lake when he reeled in the sock and discovered it contained a pineapple hand grenade with the safety pin intact, the Springfield News Leader reported Wednesday.
"I felt the weight to it and felt the ridges of the pineapple and knew what it was," said Tucker, an army veteran. "I looked at it and found it wasn't a dud -- it wasn't drilled out."
Tucker said he carefully placed the sock and its contents on some nearby rocks and reported the location to authorities.
The Springfield Fire Department bomb squad took pictures and X-ray images of the device and passed the information on to the Fort Leonard Wood Explosives Ordnance Disposal team, which arrived at 12:20 p.m.
Army Staff Sgt. Garrett Herbert retrieved the item, which he described as a "Mark 2 pineapple grenade from the Vietnam era," and it was transported to Fort Leonard Wood for disposal.
"The pin was still in it," Herbert said. "Based on the X-rays we saw, I'm going to call it armed," Herbert said.