The flames are lapping higher around Arizona Sheriff Joe Arpaio.

Arpaio, the self-proclaimed “America’s Toughest Sheriff” because of his controversial crackdown – at the county level – on illegal immigration, now is under fire again because of the critical condition of a man who became unresponsive while in the custody of his deputies. 

The man is now on life support, and “brain dead,” say published reports. His family is deciding when to take him off life support.

Arpaio's department already was under federal investigation because of complaints of deputies using excessive force against Latinos.

According to the Arizona Republic, Ernest M. Atencio, 44, was arrested by Phoenix police on assault-related charges at 3 a.m. on Friday. Maricopa County sheriff’s officials say that Atencio became combative during the booking process, requiring the police and the sheriff’s deputies to restrain him.

The sheriff’s deputy director, Jack MacIntyre, said in a statement that Atencio was taken to a safe cell where authorities hoped he would calm down, according to the Arizona Republic. When medical staff checked on him after a short while, they found him unresponsive and tried CPR and other efforts, the newspaper says.

State Sen. Steve Gallardo met with Atencio’s family, who are said to be concerned that police authorities may have used excessive force that led to Atencio’s precarious medical state, the newspaper says.

"If someone is booked in jail and they are acting up, I expect (deputies) to do what they can to subdue them; you should not end up having an individual on life support," said Gallardo, according to the newspaper.

Arpaio said his office is investigating.

"I'm not trying to avoid you, we have to do an investigation," said Arpaio, according to MyFoxPhoenix.com. "We do it all the time, we have an incident in the jails...we're going to do this one too, very professionally." 

The Daily Mail said in a story that Atencio is a Gulf War veteran. Atencio supposedly was Tasered by authorities, the news site said, attributing the assertion to Atencio’s family.

The Daily Mail also reported that homicide detectives are reviewing video of Atencio’s detention at the sheriff’s office.

The incident is the latest scandal in a streak of headline-making problems for the department run by Arpaio.

Arpaio’s boundary-pushing foray into Arizona's immigration enforcement over the last six years met its most bruising criticism when the U.S. Justice Department last week released a report that said the lawman's office carried out a blatant pattern of discrimination against Latinos and held a "systematic disregard" for the Constitution.

Arpaio, defiant and caught by surprise by the report's release, called the allegations a politically motivated attack by President Barack Obama's administration that will make Arizona unsafe by keeping undocumented immigrants on the street.

The Obama administration "might as well erect their own pink neon sign at the Arizona-New Mexico border saying welcome illegals to your United States, my home is your home," Arpaio said.

The government, which released the report after a three-year investigation into complaints about anti-Latino bias in the sheriff’s office, found that Arpaio's office committed a wide range of civil rights violations against Latinos, including unjust immigration patrols and jail policies that deprive prisoners of basic Constitutional rights.

"We found discriminatory policing that was deeply rooted in the culture of the department, a culture that breeds a systematic disregard for basic constitutional protections," said Thomas Perez, who heads the Justice Department's civil rights division.

In response, Arpaio declared at a news conference: "Don't come here and use me as the whipping boy for a national and international problem."

The fallout from the report was swift. The U.S. Department of Homeland Security announced it is severing ties with Arpaio, stripping his jail officers of their federal power to check whether inmates in county jails are in the county illegally.

Homeland Security officials also are restricting Arpaio's office from using a program that uses fingerprints collected in local jails to identify undocumented immigrants.

Arpaio has long denied the racial profiling allegations, saying people are stopped if deputies have probable cause to believe they have committed crimes and that deputies later find many of them are undocumented immigrants. He also said the decision by Homeland Security to sever ties will result in undocumented immigrants being released from jail and large numbers.

The sheriff has built his reputation on jailing inmates in tents and dressing them in pink underwear, selling himself to voters as unceasingly tough on crime and pushing the bounds of how far local police can go to confront illegal immigration.

Apart from the civil rights probe, a federal grand jury also has been investigating Arpaio's office on criminal abuse-of-power allegations since at least December 2009 and is specifically examining the investigative work of the sheriff's anti-public corruption squad. The squad launched investigations of officials, lawyers and judges who ran afoul of Arpaio, and the cases all collapsed.

Arpaio has also been under pressure from his opponents to resign in the last week after an Associated Press article brought new attention to his office's bungling of sex crime and molestation cases in a predominantly Hispanic Phoenix suburb. His office said more than 400 sex-crimes investigations had to be reopened after the department learned of cases that hadn't been investigated adequately or weren't examined at all.

Officials discovered at least 32 reported child molestations – with victims as young as 2 years old – where the sheriff's office failed to follow through, even though suspects were known in all but six cases. The cases were originally reported by The Arizona Republic and other local media and received national attention in the last week.

Thursday's report said federal authorities will continue to investigate whether the sex crimes are being properly looked at and whether the sheriff's office failed to provide adequate police services in Hispanic communities.

This story contains material from The Associated Press.

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