Aircraft registered to fictitious companies carry technology to monitor phone calls

The FBI is operating a small air force with scores of low-flying planes across the United States carrying video and, at times, cellphone surveillance technology - all hidden behind fictitious companies that are fronts for the government, The Associated Press has learned.

The planes' surveillance equipment is generally used without a judge's approval, and the FBI said the flights are used for specific, ongoing investigations. In a recent 30-day period, the agency flew above more than 30 cities in 11 states, an AP review found.