CHARLOTTE—It was in 2009 when The History Channel aired a one-hour documentary on The Hidden Valley Kings; a gang, based out of Charlotte, that once had 500 members.

Since then, not much has changed. 

"We've got some gangs that are still out of control not only in the streets of North Carolina, and we've got cartels in North Carolina, but we've also have a major gang issues in our prison system," said Gov. Pat McCrory.

On Wednesday, 12 alleged Blood gang members were arrested in Charlotte, and six of them were charged with the murder of a Charlotte-area couple. Even though they are off the street, the number of gang members in jail raises some concerns. 

"We have seen an 80 percent increase, in gang affiliations, over the last several years," said Sheriff Irwin Carmichael of the Mecklenburg County Sheriff's Office.

Carmichael says about 200 inmates, in the Mecklenburg County Jail, are gang members. All of whom are separated from one another, into individual cells, for safety reasons.

"We cannot house them together and we want to make sure that we're not allowing them to recruit new members," said Carmichael.

Gov. McCrory described the issue as “one of the best kept secrets that we have in this nation and in our state”. He said he is working with the Federal Government to figure out how to end the problem.

According to the latest National Gang Threat Assessment, there are 1.4 million active street, prison and OMGs [Outlaw Motorcycle Gang] members, making up more than 33,000 gangs in the United States.