Around 2,000 people demonstrated in the Kurram tribal area today after unmanned US drones killed at least 12 people in the region.
Protesters gathered in the main town of Miram Shah chanting: "Down with America" and "Stop drone attacks."
They threatened to attack Pakistani soldiers and block Nato supplies to occupation forces in Afghanistan if the drone strikes continue.
Tribal elder Malik Shahzada said that the US is "targeting innocent people, innocent women and children.
"We will stage a sit-in in Islamabad if the government does not take steps to stop it," he said.
CIA agents who control the drones from Langley in the US fired missiles at a vehicle in Kurram today, killing five people who Pakistani spooks said were suspected militants.
When tribesmen rushed to the scene another missile hit, killing another two people.
Minutes later another missile slammed into a nearby house and killed five others.