The mother of an alleged cartel hit man suspected of slaying at least 40 people in the U.S. and Mexico said she did not believe her son committed the atrocities he claims he did.

"This is hard for me — really hard. I'm still shaking, I'm not in a condition to deal with this," Loreta Fernández told the Los Angeles Times. “All I can say is God bless him.”

José Manuel Martínez, a self-declared hit man for an unnamed Mexican cartel, was apparently ready to talk and perhaps take the load of dozens of murders off his back.

Martinez, now 51, had been arrested last June after crossing the border from Mexico into Arizona. Shortly afterward he was sent to Alabama, where he awaited trial on one murder charge.

But then word got out, and a steady stream of investigators from across the country came to question Martinez. And he talked and talked and talked.

"In the course of interviewing him, we developed a good rapport," Lawrence County, Ala. Sheriff Gene Mitchell said, according to The Independent. "He felt comfortable talking to our investigator and, in the course of those conversations, he mentioned he had done some other things."

Charged in Central California with killing nine people, he willingly confessed to investigators earlier his week that he carried out up to 40 slayings in a career spanning decades. 

Errek Jett, the district attorney in Lawrence County, Ala., said they believe him because of the details he was able to provide.

He also informed investigators that he had been collecting debts for a Mexican drug cartel since the age of 16. And yet, as Mexican-born U.S. citizen, he carried a normal life all these years as a day laborer.

Defense attorney Thomas Turner, who represents Martinez in the Alabama case, said his client is eager to start a trial in Alabama, so he can return to California. Turner said Martinez maintains his innocence to the charge there and doesn't seem to be a hardened killer.

"I've found him to be polite and a likable individual," Turner said. "He has a good personality as far as talking with him."

Prosecutors in California say otherwise.

Martinez targeted victims in Tulare, Kern and Santa Barbara counties between 1980 and 2011, said Tulare County Assistant District Attorney Anthony Fultz, who filed charges Tuesday.

Investigators have released details of their case, saying six of the victims were killed in Tulare County, two in Kern and one in Santa Barbara. They ranged in age from 22 to 56, investigators said.

One man was shot dead in 1980 driving to work in the morning, while two men were shot in 1982 working on a ranch, one surviving. The same year, another man went missing before being found two days later by ranchers shot and stabbed to death. Yet another was found in 2000 shot to death in bed with his four children at home.

In addition to the nine murder counts, Martinez was charged in California with one count of attempted murder and the special circumstances of committing multiple murders, lying in wait and kidnapping. Four murder charges include the allegation he committed the crime for financial gain, the criminal complaint says.

The California charges would make Martinez eligible for a death sentence, if he is convicted.

Martinez has spent brief stints in state prison following a 2007 conviction on theft and drug charges, according to the California Department of Corrections and Rehabilitation.

Based on reporting by The Associated Press.

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