The United Nations, United States and Afghan government have condemned Wednesday's attack on UN Guest House in the Afghan capital of Kabul, which killed 12 people including six foreign UN staff. A separate statement said that this was handiwork of enemies of the country to deter reconstruction and rebuilding. The held-up UN Mission in Afghanistan said that it was very dark day for the UN in the country but added that the attack will not deter the world body from fulfilling its work in Afghanistan. AIR correspondent reports that one among the UN staff killed was an American worker while nationalities of other killed have not been disclosed. <br/>