United Nations Secretary General Ban Ki-moon on Tuesday criticized the killing of two South Korean hostages by Taliban militants in Afghanistan, ending a studied silence on the matter. "The secretary general deplores the killing of two of the hostages from the Republic of Korea held by the Taliban," dpa quoted UN spokeswoman Marie Okabe as saying. "He offers his sincere condolences to the family of the victims and to the Korean people." "He remains deeply concerned for the safety and welfare of the 21 Korean hostages, the German national and the four Afghans, who are still being detained," she said. "The secretary general notes that these (Korean) hostages include many young women who came to help the people of Afghanistan and they should not be made part of the conflict in that country." Okabe said Ban continues to support the Afghan government's efforts to win the release of "all those being held against their will."