According to the Guardian:
Kwon Ho Ung – Pyongyang’s chief delegate from 2004 to 2007 for ministerial talks with Seoul’s then liberal government – was executed by firing squad, Seoul’s mass-circulation Dong-a Ilbo newspaper said, citing an unidentified source in Beijing.
South Korea’s intelligence agency and the unification ministry, which handles relations with North Korea, refused to comment on the report.
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The newspaper report said it had not confirmed when and where Kwon was executed.