Inmates are carrying out drug vendettas inside prison walls, planning escapes, running their drug empires on the outside, and challenging authorities' control even at Mexico's highest-security penitentiaries.
The situation has gotten drastic enough that some leading officials are calling for the army to intervene.
Mexican prisons have always been infamous for illegal activity. Guns are often smuggled into cellblocks, guards take bribes, and authorities are just getting around to blocking cell phones, even in model prisons built in the 1990s as part of the country's war on drugs.
But chaos within the last week -- including two inmate vendetta killings -- have even federal Attorney General Rafael Macedo de la Concha admitting that problems have reached crisis level.
"What is happening is that a breakdown is occurring due to corruption," Macedo de la Concha said after Arturo Guzman, brother of fugitive drug lord Joaquin "El Chapo" Guzman, was shot to death by another inmate Dec. 31 at La Palma prison, a top security institution that's the country's showcase prison.
Just a day after Macedo de la Concha spoke, another inmate was shot to death -- again with a smuggled pistol -- at a state prison in the western state of Michoacan.
The La Palma killing was the second at the prison near Mexico City since Oct. 6 when a prisoner gunned down another associate of Guzman's with a smuggled pistol. After the latest shooting, the warden was fired; authorities detained him for questioning after he allegedly failed to cooperate with the probe.
Mexico City Mayor Andres Manuel Lopez Obrador, an early presidential front-runner for the 2006 elections, said that "given the seriousness of the situation, the army should be brought in to temporarily take over the running of the prisons," a suggestion rejected by President Vicente Fox's government.
Jalisco Governor Francisco Ramirez Acuna -- whose state includes the second-highest security prison, Puente Grande -- says he's had enough, and doesn't want any more dangerous federal inmates transferred to his state.
"They should keep them in La Palma, and enforce adequate security there," Ramirez Acuna said.
In 2001, "El Chapo" Guzman himself escaped from Puente Grande by bribing guards. Prosecutors contend that Guzman and other drug lords practically ran the prison, putting guards on their payroll and smuggling in alcohol, drugs, prostitutes -- even Viagra.
The credibility of prison officials has gotten so bad that on Thursday, when police beefed up a security cordon around Puente Grande, rumors flew that its highest-profile inmate had escaped -- and authorities had to show a video of him in custody to quell the rumors.
The inmate -- Rafael Caro Quintero, serving a 40-year sentence for the torture-murder of a US Drug Enforcement Agency agent -- was among dozens of inmates moved to Puente Grande in August after evidence emerged of a planned jailbreak at La Palma.
Officials argue the new seriousness of Mexico's anti-drug enforcement is apparent since the leading drug figures remain in jail.
But the officials also acknowledge that the drug dealers still are dangerous.
"Some inmates, because of the economic power and organizational strength of their gangs, put prisons under a great deal of pressure," Macedo de la Concha said.