(2nd LD) Seoul takes heed of N.K.'s 'rare' direct criticism of China
(ATTN: EXPANDS time line; UPDATES with China's reactio in paras 6-9)
SEOUL/BEIJING, May 4 (Yonhap) -- South Korea's unification ministry said Thursday that it was rare for North Korea to directly criticize China, one day after Pyongyang claimed that B