An outdoor advertising company that owns thousands of billboards across the country, including in Times Square, and around the world, is using mobile photo data to learn about people who are passing their displays in order to cater ads to specific consumers, and U.S. Sen. Charles Schumer wants federal officials to investigate if the practice is legal.

The company, Clear Channel Outdoor Americas, which has more than 675,000 displays in more than 40 countries, insists the information it uses is anonymous. The company said it launched a service that works with partner companies to match aggregated cellphone location data to maps of its billboards, so the company can gather information about the people who pass its displays and tell whether those people eventually end up visiting the advertiser's stores.

The program, known as Clear Channel Outdoor RADAR, is a partnership between the outdoor advertiser and several companies, including AT&T and a technology corporation that uses location data collected from other smartphone apps, in order to track the travels and behaviors of consumers through their phones.

Schumer says he believes the company has created "spying billboards." The New York Democrat is asking the Federal Trade Commission to launch an investigation to determine whether the tracking constitutes a deceptive trade practice.

In a video on its website, the company says it "measures consumer's real-world travel patterns and behaviors as they move through their day, analyzing data on direction of travel, billboard viewability, and visits to specific destinations." That information, the company says, is then mapped against Clear Channel's displays, which would allow advertisers to buy ads in places that would "reach specific behavioral audience segments."

Clear Channel uses "aggregate and anonymous mobile consumer information," the company said. The program gives marketers a "solution that provides a more accurate way to understand and target specific audience segments," Clear Channel's vice president, Andy Stevens, said in a news release announcing the initiative in February.

The company insists the data it is mining from its partners is used to gather information about the average viewer of specific billboards and that individual consumers cannot be identified.

But Schumer wants an investigation because, he says, most people don't realize their location data is being mined, even if they agreed to it at some point by accepting the terms of service of an app that later sells their location information.

"A person's cell phone should not become a James Bond-like personal tracking device for a corporation to gather information about consumers without their consent," Schumer said. "No one wants to be followed or tracked throughout their day, electronically or otherwise, so these new billboards not only raise eyebrows, but they raise some serious questions about privacy."

Schumer, who is set to formally announce the call for an investigation at a news conference later Sunday, said consumers should also be allowed to opt out of the location monitoring.

Clear Channel and the Federal Trade Commission did not immediately respond requests for comment.