SADO, Japan (AP) — South Korea paid tribute to wartime Korean forced laborers at Japan’s Sado Island Gold Mines in a memorial ceremony on Monday, a day after boycotting a similar event organized by Japan, as tensions over historical atrocities continue to impact relations between the two sides.

SADO, Japan (AP) — Japanese officials on Sunday paid tribute to workers at the country's Sado Island Gold Mines but offered no apology over Japan’s brutal wartime use of Korean forced laborers, highlighting lingering tensions between the neighbors over the issue.

A memorial service for Korean laborers forcibly mobilized to the Sado mines, which Japan had promised to hold annually following the site’s inscription as a UNESCO World Cultural Heritage last summer,

The Korean government held its own ceremony on Monday to honor Korean wartime forced laborers at their former lodgings near Japan’s Sado Mine, following Seoul’s decision to boycott a Japan-hosted memorial held on Sunday.

South Korea’s government says it has decided not to attend a memorial service near Japan’s Sado Island Gold Mines due to unspecified disagreements with Japan over the event, which stirred longstanding tensions over the abuse of Korean forced laborers at the site before the end of World War II.