Santa Ana, California -- The inmates had to heat the letter to draw out the message, written in invisible ink. When they did, their orders were clear.
Within hours, prosecutors say, members of the Aryan Brotherhood prison gang sneaked into a nearby cellblock and killed two black inmates with handmade shanks as part of an order to "go to war" with blacks.
The deaths are two of the 32 murders and attempted murders detailed by federal prosecutors in a sweeping case against the Aryan Brotherhood, a violent white supremacist prison gang that has infiltrated nearly every federal and state prison since its beginnings in San Quentin in 1964.
Prosecutors hope to dismantle the gang -- nicknamed the "Brand" -- in a series of trials that together make up what's believed to be the biggest capital murder case in U.S. history. Of the 40 men initially charged, as many as 16 could face the death penalty for crimes that reach back 30 years.
Prosecutors are pursuing the highly organized gang with a racketeering law originally passed to target Mafia leaders -- a tactic recently used with some success against other prison gangs in California and Texas.
"We're looking at this huge list of charges, and I'm unaware of any other case that's even close to this," said Dean Steward, attorney for Barry "The Baron" Mills, a lead defendant.
Opening statements in the trial of Mills and three others are scheduled to begin March 14 in federal court in Santa Ana. Mills and another alleged ringleader, Tyler "The Hulk" Bingham, face the death penalty in what could be a nine-month trial.
Four more defendants are set to go on trial in Los Angeles in October; court dates in California are pending for the remaining men. Nineteen of the 40 defendants struck plea bargains, and one has died.
The 140-page indictment against the gang alleges a web of conspiracies to murder fellow inmates who offended gang members, cheated them on drug deals, failed to comply with the orders of leaders or snitched to prison authorities. Prosecutors, who declined to be interviewed, spent six years compiling evidence and relied on informants for much of their case.
Court documents suggest that patient gang members waited months to carry out the violent tasks ordered by their leaders, passing information from prison to prison and member to member using friends and spouses on the outside, corrupt prison guards and notes written with invisible ink.
In one case, for example, members of the Aryan Brotherhood allegedly spent a year planning the murder of Richard Barnes, the father of a fellow gang member who had testified against the gang. Members funneled his address and firearms to someone on the outside, who shot him in the head in 1983, according to court documents.
"This has the potential of being incredibly damaging to the brotherhood," said Joanna Mendelson, an investigative researcher with the Anti-Defamation League, which tracks the Aryan Brotherhood. "They rank among the most organized, systematic gangs in all the prison system."
Mills, who faces a number of charges in the current case, has already been convicted of luring another inmate into a recreation shack at a federal lockup in Atlanta in 1979 with the promise that he would get a new tattoo.
Instead, Mills nearly decapitated the man with a handmade knife -- his punishment for cheating the brotherhood on a drug deal, according to court documents.
Mills, now 57, went on to become a founder of a three-member group that prosecutors say ordered and approved murders carried out by gang members or aspiring members. He is currently serving two life terms for the 1979 murder, which is detailed in the indictment as part of the government's racketeering case.
Mills, Bingham and the others going to trial have pleaded not guilty.
"The reality is, federal penitentiaries are violent and dangerous places and all of these guys -- white guys -- are a small minority and they're just trying to survive," Steward said.
Civil rights groups that monitor the Aryan Brotherhood say highly disciplined gang members managed to communicate frequently, despite 23 hours a day in solitary confinement.
Accused members often acted as their own attorneys and subpoenaed other brotherhood members to testify, allowing them to pass messages in court through hand signals and code words or slip messages into legal files, said Melissa Carr, an expert on the gang with the Anti-Defamation League.
Some gang members write messages to outside helpers using coded alphabets or invisible ink made with their own urine, she said, while others pass tiny messages on a string, called "kites," from one cell to another when guards aren't looking.
Experts say prosecutors will face challenges in their push for death penalties -- particularly because nearly all the victims were convicted felons and many defendants are already serving long prison terms.
"The jury says, 'Well, these people are in prison already and if they kill other prison inmates, who cares?"' said William McGuigan, a defense attorney who has worked on several Mexican Mafia cases. "They aren't outraged like they are if the victims are ordinary citizens."