full identities not known
"The expanded authority, approved two years ago by the Bush administration and continued by President Obama, permits the agency to rely on what officials describe as "pattern of life" analysis, using evidence collected by surveillance cameras on the unmanned aircraft and from other sources about individuals and locations. The information then is used to target suspected militants, even when their full identities are not known, the officials said. Previously, the CIA was restricted in most cases to killing only individuals whose names were on an approved list." (thanks Dina)