The Afghan government, earlier, blamed the Taliban who attacked the Bakhtar guest house, where 34 UN staffers were residing, on October 28 last year in which five UN personnel were killed.
Three of them are believed to have died in "friendly fire" by Afghan security forces. Another staffer was burnt in a fire that was caused by exploding grenades, the Board of Inquiry revealed.
However, it remains uncertain how Close Protection Officer Louis Maxwell was killed although the investigation leans towards the scenario that he could have been killed by Afghan forces due to mistaken identity.
"It is not clear how Maxwell was killed," Susana Malcorra, Under-Secretary-General for Field Support, told media persons in New York.
"Even though there is a strong sense that he may have been killed by some Afghan police."
The final report, which investigates the killings, has been submitted to Secretary-General Ban Ki-moon and the Afghan government but not been made public.
A video, procured by the UN in January, shows Maxwell, 27, being shot while surrounded by Afghan police. As the victim collapses to the ground the police around him do not move.
Maxwell, who was firing back at the militants to allow others to escape the guesthouse, was killed by long-range fire and not shot at close-range, according to the recent investigation.
Responding to concerns that UN had not been transparent about the role of the Afghan forces in Maxwell's death, Malcorra refuted the notion that the UN had been discreet so as not to disrupt the political channels with the Afghan government.
"The Secretary-General asked me to proceed with due process in managing this very very sad situation," she said, adding, "We haven't at all influenced the Board of Inquiry findings."Court lifts life ban on Salim Malik
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