North Korean judoka Ri Kyong Ok, who lost to Japan's Ryoko Tamura in the women's 48-kg final at the Munich meet in 2001, has pulled out of the upcoming judo World Championships, organizers said Friday. Ri, who was considered one of Tamura's rivals in the biannual tournament which gets under way at Osakajo Hall next Thursday, decided not to compete citing an injury sustained recently. Details of the injury were not disclosed.