The United States says it shares Afghan President Hamid Karzai's concerns about civilian casualties caused during fighting in that country. Karzai has fired two Afghan army officers following a joint Afghan-US-led coalition operation that he says killed at least 89 civilians. White House spokesman Tony Fratto told reporters Monday that NATO forces in Afghanistan "take every precaution to try to avoid innocent civilian casualties." Asked about Karzai's concerns about civilian casualties, Fratto said an investigation is under way. He said the US Defense Department believed "it was a good strike." He had no details on the number of dead civilians.