SACRAMENTO (CBS SF) – With black market cell phones helping some of California’s most dangerous criminals stay connected to the outside world, corrections officials have announced a plan to block illegal cell phone calls by inmates.

The California Department of Corrections and Rehabilitation announced a deal with Alabama-based Global Tel Link (GTL) to block cell phone and Internet communication in prisons while providing some authorized cell phone access for a fee.

Revenue from those calls will fund the GTL  system to prevent unauthorized calls, text messaging and wireless Internet access, curbing a problem that’s plagued California prisons for years.

Some 15,000 contraband cell phones were confiscated from state prisons in 2011, said Sgt. Anthony Roman, a spokesman for the state prison system.

“At least half of them have some type of Facebook app on here that these guys are running and using,” Roman said.

Roman said prisoners have been able to organize crime rings, set up murder hits, and, in the case of sex offenders, stalk their victims.

“On a couple of occasions, we’ve had to talk to a few inmates that have been bothering the victims of the crimes,” he said.

The Global Tel Link system blocked more than 25,000 unauthorized cell phone calls when it was tested at two California prisons in 2011. Officials expect the system is expected to be in place throughout the state by the end of the year.

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