HARBIN, May 12 -- A month long China-Russiasearch began Tuesday to locate the remains of Soviet Union soldiers who died in China fighting Japanese invaders in 1945.

The search centered on a 32 square kilometer area on Huoshao Mountain, in Muling City in the northeast province of Heilongjiang, where 413 Soviet Union soldiers died fighting Japanese troops in August 1945, according to a statement from the foreign affairs office of Mudanjiang City, which administers Muling.

A 17-member Russian team, along with a group of Chinese archaeologists, are involved in the dig, said the statement.

A preliminary search in April identified at least 15 sites where skulls, bones, bullets and mortar shrapnel were discovered.

In August 2012, local farmer Liu Guanglin found four bodies that were later confirmed to be Soviet Union soldiers.