The death toll from three days of U.S. drone attacks inside Yemen has reached at least 55. The victims were described as suspected al-Qaeda militants, except for three civilians who were killed in Saturday’s initial attack. The Yemeni government says the militants were plotting violence against civilian and military targets. At the White House, Press Secretary Jay Carney refused to offer details.

White House Press Secretary Jay Carney: “Again, without speaking about specific operations, I can tell you that in May 2013 President Obama spoke at length about the policy and legal rationale for how the United States takes direct action against al-Qaeda and its associated — associated forces outside of areas of active hostilities, including with drone strikes. And as the president made clear, we take extraordinary care to make sure that our counterterrorism actions are in accordance with all applicable domestic and international laws and that they are consistent with U.S. values and policy.”

Yemeni forces also reportedly took part in the operation with ground raids. The drone strikes appear to be the largest carried out in Yemen this year.