The Aryan Brotherhood of Texas has been mentioned as a possible group behind the recent slayings of Kaufman County authorities.
There's no hard evidence of a connection, but a federal racketeering indictment filed in Houston last year named more than two-dozen alleged members of a white supremacist prison gang for a range of crimes.
After the indictment there was a warning to law enforcement across Texas: be careful.
Tarrant County sheriff Dee Anderson's department was one of those agencies warned that the group may retaliate for the 34 charges leveled at its members.
"We took precautions at that time, but nothing like what's happening now," Anderson said.
The indictment details the modern world of organized crime. The Aryan Brotherhood was born in the 1980s in California prisons. The group has a constitution and membership is for life. Criminal activities range from murder to kidnapping, assault to drug and weapons trafficking, arson to counterfeiting.
There is a well-defined hierarchy in and out of Texas prisons according to experts.
"They've always had a very good intelligence network from within the prison system," said Danny Defenbaugh, a security expert. "Just because they've been arrested doesn't mean that some of that leadership still doesn't have control."
Experts say beatings and killings are one way the group maintains control against other members, usually for things like stealing drugs or cooperating with authorities.
Members of law enforcement and their spouses are not targeted, historically, but the fear is that could be changing.
Local agencies, like the Tarrant County Sheriff's Office, have come up with contingency plans and increased security.
Experts aren't sure if this is a one-time attack on a specific agency or whether the violence in Kaufman County signals a sea change in attacks against law enforcement.