Warning—again: Old war souvenirs, grenades, weapons, bullets and dynamite stored in the attic of a war veteran could be dangerous. A World War I-era explosive was removed from a Pennsylvania antiques auction on April 20, 2013, when someone realized it was a German “potato masher” stick grenade. State police took it away. The grenade was a type used from about 1918 to 1945. It looks like a long stick, but it has an explosive head and a cord at the end of the handle that could set off an explosion. The blast itself caused damage when early versions of the grenade were used. Later grenades were made with a metal sleeve that blew apart, sending shrapnel to cause more injuries. Some types could be thrown about 40 yards, useful against soldiers in trenches.