Afghanistan: New surveillance technology can track everyone in an area for several hours at a time --- DAYTON, Ohio — Shooter and victim were just a pair of pixels, dark specks on a gray streetscape. Hair color, bullet wounds, even the weapon were not visible in the series of pictures taken from an airplane flying two miles above. -- But what the images revealed — to a degree impossible just a few years ago — was location, mapped over time. Second by second, they showed a gang assembling, blocking off access points, sending the shooter to meet his target and taking flight after the body hit the pavement. When the report reached police, it included a picture of the blue stucco building into which the killer ultimately retreated, at last beyond the view of the powerful camera overhead. -- “I’ve witnessed 34 of these,” said Ross McNutt, the genial president of Persistent Surveillance Systems, which collected the images of the killing in Ciudad Juárez, Mexico, from a specially outfitted Cessna. “It’s like opening up a murder mystery in the middle, and you need to figure out what happened before and after.” -- As Americans have grown increasingly comfortable with traditional surveillance cameras, a new, far more powerful generation is being quietly deployed that can track every vehicle and person across an area the size of a small city, for several hours at a time. Although these cameras can’t read license plates or see faces, they provide such a wealth of data that police, businesses and even private individuals can use them to help identify people and track their movements. -- Already, the cameras have been flown above major public events such as the Ohio political rally where Sen. John McCain (R-Ariz.) named Sarah Palin as his running mate in 2008, McNutt said. They’ve been flown above Baltimore; Philadelphia; Compton, Calif.; and Dayton in demonstrations for police. They’ve also been used for traffic impact studies, for security at NASCAR races and at the request of a Mexican politician, who commissioned the flights over Ciudad Juárez. -- Defense contractors are developing similar technology for the military, but its potential for civilian use is raising novel civil liberties concerns. In Dayton, where Persistent Surveillance Systems is based, city officials balked last year when police considered paying for 200 hours of flights, in part because of privacy complaints.