Army Times has the story.  Excerpt:

A helicopter attack that killed at least 15 civilians in Afghanistan's Oruzgan province was called in by a Special Forces A-team that did not have "eyes on" their target and resulted in a 48-hour standdown for U.S. special operations forces, said an Army officer familiar with the incident.

In the wake of the incident, the commander of coalition and U.S. forces in Afghanistan, Gen. Stanley McChrystal, apologized to Afghan President Hamid Karzai and then to the Afghan people in a Feb. 23 television address. "I have instituted a thorough investigation to prevent this from happening again," McChrystal said.