Subscribe | UPI Odd Newsletter Subscribe UFA, Russia, Sept. 2 (UPI) -- Police in Russia said a group of teenagers found a strange object while swimming and took it home, only to discover it was a live World War II artillery shell. Authorities in the southern Urals Republic of Bashkortostan said the four teens found the object while swimming in a local pond and took it home, where they researched it on the Internet, RIA Novosti reported Monday. Advertisement The teenagers identified the device as a World War II artillery shell and called police, who were then able to confirm the device was live. A police bomb squad carried out a controlled explosion on the device. Police said an investigation has been opened into the origins of the shell, as it was located far from any World War II battle sites.