NORTH WAZIRISTAN - At least four suspected militants were killed in a US drone attack at tehsil Datta Khel in North Waziristan Agency on Wednesday. Sources said that the US unmanned aircraft fired at least two missiles on a vehicle at Datta Khel tehsil in the NWA killing four militants on the spot. The source maintained that it was a moving vehicle which was hit with two missiles. As a result, the vehicle was destroyed completely. Before the attack, the drones had hovered over the areas for some time. The sources said that it was so difficult to identify those killed in the attack. It is worth mentioning here that in the last four days it was the US drone attack in NWA. It to be noted that these missile attacks by drones have been stepped up as more than 100 drone strikes killing over 670 people in 2010 compared with 45 strikes that killed 420 in 2009. Similarly, the same attacks also continued during the current year.