Some reports even say US drone operations in Yemen nearly tripled in 2012 compared to the previous year.
The United States also carries out targeted killings through drone strikes in Afghanistan, Pakistan, and Somalia.
Eight people have been killed in the latest US assassination drone attacks in the Yemeni province of Marib.
Yemeni military officials said that the attacks were carried out by two American unmanned aerial vehicles in Abieda valley in the central province late on Saturday.
Local residents also said that two Saudi nationals were among the victims of the drone strikes.
Speaking on condition of anonymity, the local residents said that three of the bodies were burnt beyond recognition.
The US has increased the number of its drone attacks in Yemen.
Washington claims the drones target militants but local officials and eyewitnesses say civilians are mostly the victims of such attacks.