( CNN ) -- As investigators scramble to figure out who killed two Texas prosecutors , suspicions abound over whether the Aryan Brotherhood of Texas played a role . Authorities have not officially linked the two slayings , nor do they know whether the white supremacist group ordered the attacks . But a series of events leading up to the killings have raised questions about the group 's possible involvement . Here 's a primer on the Aryan Brotherhood of Texas : . What is the Aryan Brotherhood of Texas ? The FBI describes the group as a `` whites only , '' prison-based gang that has been operating since at least the 1980s . `` I think the Aryan Brotherhood of Texas today is arguably the most violent white supremacist prison gang out there , '' said Mark Potok of the Southern Poverty Law Center . The group has been blamed for more than 100 homicides and at least 10 kidnappings since the early 1980s . Is the Aryan Brotherhood of Texas part of the Aryan Brotherhood ? No . Inmates in Texas asked the Aryan Brotherhood , a California-based prison gang , for permission to start a Texas chapter , but they were denied membership , the Southern Poverty Law Center said . It 's not clear why . Nonetheless , the Texas-based group modeled itself after the California gang . What does the Aryan Brotherhood of Texas stand for ? Like the Aryan Brotherhood , the Texas group 's main purpose morphed from protecting white inmates to criminal activities involving drugs , extortion and murders , authorities say . It also espouses a white supremacist ideology . `` At the end of the day , these organizations are really fundamentally criminal enterprises , '' Potok said . `` That means , above all , their interest is in green . In money . Skin color comes long after that . '' Its reach began to extend outside prison walls as more members finished their sentences . ABT members on parole are required not only to remain loyal to the gang , but also to recruit new members . `` Brutal beatings , fire bombings , drug trafficking and murder are all part of ABT 's alleged standard operating procedures , '' said Lanny Breuer , a former Assistant U.S. Attorney General . Did the group play a role in the deaths of Kaufman County District Attorney Mike McLelland and Assistant District Attorney Mark Hasse ? Authorities do n't know . But McLelland 's office was one of numerous agencies involved in a multi-year investigation that led to the indictment of 34 alleged members of the ABT -- including four of its senior leaders -- on racketeering charges in November . At the time , Breuer called the indictment a `` devastating blow '' to the organization . Weeks later , the Texas Department of Public Safety issued a statewide warning saying it had `` credible information '' that members of the group were planning to retaliate . In an interview with The Associated Press after Hasse 's death , McLelland said his deputy had n't been involved in the Aryan Brotherhood of Texas investigation . But the district attorney nevertheless raised the possibility the group was behind the death . `` We put some real dents in the Aryan Brotherhood around here in the past year , '' McLelland told the news agency . How do members join the Aryan Brotherhood of Texas ? `` It is said to be one of the gangs that live by the 'blood-in , blood-out ' code , meaning that you can only get into ABT by carrying out some kind of attack , '' Potok said . `` And similarly ... you can only leave in a body bag . '' CNN 's Ed Lavandera contributed to this report .
The Aryan Brotherhood of Texas has been blamed for more than 100 homicides . In the past year, a number of white supremacists have also carried out attacks in other states, including California, Florida and Texas. The Kaufman County DA 's office had helped prosecute some of the gangs ' members . The Aryan Brotherhood of Texas was denied membership in the Aryan Brotherhood .