Home Guards practicing throwing hand grenades from a sunken railway track doubling as a trench. Credit: M. McNeill / Fox Photos / Getty Images

A family near Kalamazoo, Michagan was in for a surprise while cleaning out their grandfather’s basement. Amid the dusty storeroom clutter, the Paw Paw Township residents discovered a vintage, possibly live grenade from World War II apparently forgotten after decades in storage. Unsure what to do with their newfound, potentially deadly device, family members quickly contacted local emergency services.

According to the Van Buren County Sheriff’s Office , first responders confirmed the grenade’s authenticity and estimated that it dates back to 1945. However, they couldn’t immediately determine if the weapon remained functional after more than 80 years tucked away in the cellar.…