A U.S. drone strike targeting al Qaeda suspects in Yemen killed 13 civilians, including three women, three security officials in the restive Middle Eastern country said.

"This was one of the very few times when our target was completely missed. It was a mistake, but we hope it will not hurt our anti-terror efforts in the region," a senior Yemeni Defense Ministry official told CNN. The official asked not to be named because of the sensitivity of the issue.