Moscow, Apr 17 (IANS/RIA Novosti): A dog has dug up a large cache of old Japanese munitions on Russia's Sakhalin island, police said.

"About 500 Japanese shells, as well as numerous ammunition cases and cartridges, were found some 200 metres from the 29th km of the Yuzhno-Sakhalinsk-Sinegorsk highway," a police representative said.

It was not immediately clear how old the ammunition is. Police have cordoned off the area before deciding what to do with the munitions.

Sakhalin was a disputed territory between Russia and Japan for several decades in the 19th and 20th centuries. Japan gained the southern part of the island after the Russo-Japanese war in 1905.

After that conflict, the two states signed a treaty in 1905 under which Japan gained the island's southern part in 1907, with the former Yuzhny Sakhalin renamed Karafuto Prefecture.

At the end of World War II, the Soviet Union took control of the whole island, expelling Japanese forces.