The FBI's most wanted bank robbers, violent criminals and terrorists will soon appear on 150 digital billboards in 20 cities across the United States.

The agency has teamed up with Clear Channel Outdoor to begin airing mug shots following a successful test run in Philadelphia that led to several arrests.

One of those arrests was of a man suspected in the fatal shooting of a Philadelphia police officer, the agency said Thursday. He was captured in Florida as a result of exposure on the billboard, the FBI said.

"We'll target very violent, dangerous fugitives," said Scott Wilson, spokesman for the Cleveland FBI office.

Cleveland, Atlanta, Indianapolis, Los Angeles and Newark, New Jersey, are among the cities where the advertising company has electronic billboards along major roadways. This is the first time the FBI is posting its fugitives.

The company is donating the eight-second spots, which will also feature photographs of missing children. The company can add new information to the signs within minutes.

Clear Channel Outdoor will pre-empt paid advertising if the FBI needs to broadcast an urgent message, the company's global president Paul Meyer said.

The use of electronic billboards in crime fighting has spread across the U.S. in recent years, and criminals have been known to turn themselves in after seeing their photos.

There are about 800 such boards nationwide, according to the Outdoor Advertising Association of America.