North Korea has executed a number of senior officials involved in failed talks with the US in Vietnam, according to a report. The second summit between Kim Jong Un and Donald Trump ended in failure back in February, with the two leaders walking away from negotiations in Hanoi due to a dispute over sanctions. South Korean newspaper the Chosun Ilbo said Kim Hyok Chol, the special North Korean envoy to the US, and other officials who carried out working-level talks during the summit were held responsible by Pyongyang for its collapse and were killed as part of a massive purge in March. The Choson Ilbo said the killings were carried out to divert attention away from internal turmoil and discontent, with a recent UN report claiming the country's population is living in a 'vicious cycle of deprivation, corruption and repression'.