ACE Checkzone: The Enforcement Zone double-click video to start, click to pause. In this clip, a produce truck has entered the Enforcement Zone. The driver is led out of the truck and held nearby for questioning. Meanwhile, other soldiers approach and move to inspect the back of the truck. While there are no explicit uses of new sensor technology in this scene, the information gathered in previous zones has directed soldiers to check the payload for possible explosives. Although not developed here, additional sensor nodes could be in place to record further information to help soldiers assess the threat of the vehicle and of the driver and passengers. Videos require Quicktime. Narrative Vehicles at this time were being sent to the Enforcement Zone at a rate of about 10 per hour. This represented approximately 14% of all vehicular traffic. Some vehicles sent to Zone 3 were observed to be carrying large loads of food and supplies, and were sent there because of their vehicles' excessive weight and the inability of the drivers to communicate with the soldiers in Zone 2. After examining the payload and questioning the driver, all of these vehicles were allowed to continue. Another large truck is directed to enter the Enforcement Zone, and it appears to also be carrying large amounts of produce. Reports indicate that just like many of the previous vehicles, this one was also overweight and there was an inability to communicate with the driver. The one difference with this vehicle is that it had passed through the same checkzone in the early morning hours, and was allowed to proceed after inspection. When the vehicle is stopped, the driver is asked to get out and does so, along with 2 other passengers who were not in the vehicle when it came through earlier. The truck's payload of dirt, claimed to be for a construction project is searched. Buried in the mound are relatively small containers of explosive chemicals with electrical wire running under the car to the engine block and gas tank. The vehicle occupants are further detained while the area is cleared and the vehicle disarmed. It is then moved off the road to make way for further inspections. The Enforcement Zone identical in many ways to traditional TCPs. The main difference is that vehicles that enter this zone are already suspicious for one reason or another. After weeks of operations, a small sedan is directed to enter the Enforcement Zone very early one morning. Traffic is nonexistent (5-10 vehicles per hour) and because of this soldiers had adopted the policy of thoroughly checking every vehicle in Zone 3 no matter the readouts from Zones 1 and 2. This particular vehicle belonged to a commuter. It was seen passing through the checkpoint 12 times in the past 3 weeks. This time however, the driver seemed agitated and anxious, and during a search of the vehicle a large cache of gunpowder and 10 automatic rifles were found under the seats. After-Action Reviews (AARs) revealed other similar occurences, indicating that the enemy had begun using vehicles that have cleared security multiple times to hide their actions. This trend was revealed to be an effective means of clearing the checkzone with as little scrutiny as possible.