Updated

Cameras catch red-light runners at intersections and grab images from light poles in mall parking lots and near gas station pumps. All those roaming eyes mean the getaway vehicle of the Washington-area sniper and probably the killer himself are on some tape, somewhere.

Now military surveillance planes are pitching in, putting the area under still more scrutiny in a manhunt frustrated by a killer's luck and skill in slipping out of sight.

Officials won't acknowledge how consequential such surveillance is to an investigation covering nine deaths and two people wounded in Maryland, Virginia and Washington.

But they are known to be obtaining footage taken from stores, banks and buildings near the shooting sites. Investigators have also viewed images from cameras normally used to monitor traffic flow, as well as tapes from police cruisers that responded to the latest shooting, Monday night in Virginia.

The average American is caught on camera eight to 10 times a day, law enforcement officials say.

If that statistic is right or even close, "it would seem a pretty good chance that the killer would probably be on a camera somewhere," said Dave Lang, a video forensics expert at Veridian Corp. in Arlington, Va., which works with law enforcement agencies.

In response to the shooter's audacious attacks at shopping malls, gas stations and a school, businesses are adapting their security measures to deter the sniper from preying on customers. Some area gas stations are pointing cameras away from the pumps and into the space beyond in hopes of nabbing the sniper on film.

Video forensics examiners caution that adjusting a camera angle might prove futile if the technology cannot pick up images from farther away. As it is, cameras are often clumsily set up, catching the tops of people's heads instead of their faces.

In the sniper case, ground-based cameras are now being supplemented with surveillance from the sky.

Defense Secretary Donald H. Rumsfeld has approved the use of the Army's RC-7 Airborne Reconnaissance Low plane and at least one other type of aircraft with surveillance capabilities beyond those of local police forces, defense officials said.

The four-engine RC-7, can provide high-resolution imagery and night vision, suitable for tracking the light-colored van that investigators have linked to the shootings. It also has the benefit of looking like many other small planes, so it won't stand out, and its infrared sensors can detect gunfire on the ground.

Whether human eyes or cameras eventually provide a break in this case, one thing remains certain: Surveillance in public places is becoming more prevalent as the technology improves and becomes more affordable.

Montgomery County, where five of the sniper's victims were shot, rotates about a dozen red light cameras around 15 locations, and has other cameras in many more places to view traffic.

Police are not saying how helpful all those lenses have been thus far in the hunt for the sniper.

"It may provide the law enforcement or the authorities a hint, a clue as to who may be doing this, but it's not the answer to their questions," said Alex Tabb, associate managing director of Kroll Inc., a security consulting firm. "It's not, 'Let's throw video cameras everywhere and we'll be safe."'

The best known descriptions of the sniper have come from eyewitnesses to Monday night's slaying of 47-year-old Linda Franklin of Virginia in a Home Depot parking lot in Falls Church, Va.

Home Depot spokesman John Simley refused to specify whether that store has outdoor cameras, but said most stores in the chain have indoor monitoring, primarily to catch shoplifters or false injury claims.

"We've shared any and all evidence with the police that they have requested," he said.

Kroll managing director Blake Coppotelli, a former prosecutor, said businesses tend to spend money on indoor surveillance rather than on cameras in the parking lot.

"There are a number of homicides I have worked on that would have been quite easy to solve had there been surveillance cameras on the outside," he said.

Surveillance technology is being increasingly employed in criminal investigations.

Sept. 11 hijackers Mohamed Atta and Abdulaziz Alomari were seen getting money from bank machines, a gas station and a Wal-Mart the day before the attacks. Last month, a camera in an Indiana parking lot showed a woman, later charged, hitting and shaking her young daughter.

In Tampa, Fla., and Virginia Beach, Va., face recognition technology compares people in crowds with a database that includes wanted criminals.

That has brought complaints from civil liberties groups and citizens concerned about having their every move recorded, whether walking through the park or running a red light.