WASHINGTON (Reuters) - U.S. Defense Secretary Jim Mattis said on Thursday the U.S. military did not have all the accurate information on an ambush in Niger earlier this month that killed four U.S. soldiers. “The loss of our troops is under investigation,” Mattis said before a meeting with his Israeli counterpart at the Pentagon. “We, in the Department of Defense, like to know what we are talking about before we talk and so we do not have all the accurate information yet.”  “We will release it as rapidly as we get it,” he added. 