Between ads for Trident Technical College and Saturn automobiles, an urgent appeal flashes across an enormous screen: "Have you seen me?"

North Charleston police are using a 14-by-48-foot digital billboard to solicit leads on missing people and wanted suspects. Billboard owner Adams Outdoor Advertising started donating space on the sign facing eastbound on Interstate 26 near Ashley Phosphate Road about a month ago.

"Everybody wins," said the company's general manager, Jon Kane. "The

technology actually allows you to do it within a couple of minutes."

The technique has yielded results for police elsewhere in the country.

Lately, the sign on I-26 has been showing pictures of two missing North Charleston women: Viridiana Maldonado, 22, who disappeared Oct. 11, and Brandy Hanna, who disappeared May 20, 2005, and would now be 35 years old.

When detectives were searching for two cousins on murder charges last month, they briefly put their pictures on the screen. Though the pictures didn't lead directly to their capture, the department plans to use the display again for suspects in violent crimes, public information officer Spencer Pryor said.

The billboards are a bit like a small movie screen or a giant television, but when the image isn't changing, it can be hard to distinguish from traditional signs. With the old-style billboards, it takes about five days under the best of circumstances to change the image, Kane said. With the new ones, the company can, in theory, post content within minutes of receiving an e-mail.

Adams began using the digital billboards last spring and now has eight in the Charleston area, Kane said.

The one North Charleston police are using could have potentially been seen by more than 100,000 people on an average workday — about 25 percent of the Charleston metro area's adult population.

The company has been talking to state and county officials about activating the signs during Amber Alerts, giving authorities a way to post photos of people and vehicles in serious child-abduction cases.

"It would pre-empt the advertising," Kane said.

The same concept could be applied during severe-weather emergencies.

Reach Noah Haglund at 937-5550 or nhaglund@postandcourier.com.