The attack Wednesday in the Bannu region of Pakistan -- the first outside the tribal regions along the Afghan border -- left five people dead.

CNN said the attack by an unmanned aircraft killed at least three non-Pakistanis although it was not clear if they were connected to al-Qaida or Taliban elements that have been fighting coalition forces in Afghanistan.

The attack was the third U.S. attack reported inside Pakistan this month and was condemned on the floor of the parliament Thursday as a violation of Pakistani sovereignty.

Ambassador Anne Patterson heard a formal protest from the government last month after 20 people were killed in a similar attack by an unmanned drone.