PHOENIX -- The Arizona Department of Public Safety has unveiled a new, statewide photo enforcement program at a news briefing on Thursday morning.

The program will be the first photo enforcement program in the U.S. administered by a state-level law enforcement agency, DPS said.

Safety experts said no U.S. state has implemented the automated equipment on a broad scope to enforce speed limits on freeways or open stretches of highways.

The Arizona program will launch with photo radar vans -- hybrid mobile vehicles that contain all the components necessary to catch speeders on camera.

"One of the things we will not announce is where these vehicles are going to be, although signage will be in place," said DPS Director Roger Vanderpool.

The vans will be in place Thursday afternoon or Friday morning. One of the first locations will be along State Route 347, DPS said.

After Thursday, DPS said it will not announce the location of the photo enforcement vehicles in advance.

The program would only affect traffic enforcement on Arizona highways, not on surface roads through the state's cities and towns.

The primary decision of where to put them will be based on roadways with the most accidents and those with construction zones.

Eventually CPS will set up fixed photo-radar units on some freeways.

Citing decreased speeding and accident rates during Scottsdale's placement of speed cameras on a stretch of the Loop 101 state freeway in that city, Gov. Janet Napolitano on Jan. 24 announced she was directing DPS to work with the Department of Transportation to launch the state program.

Vanderpool was joined by Commander Thomas Woodward and representatives of Redflex Traffic Systems at Thursday's news briefing at DPS headquarters in Phoenix.

Redflex is a private vendor based in Scottsdale that will administer the program for the state.