The inmate who was found not breathing at the jail run by the controversial Maricopa County Sheriff's Office has died after being taken off life support.

Ernest Atencio, 44, was booked into jail Thursday night when deputies said he became combative and had to be placed in a "safe cell."

Fifteen minutes later, he was found unresponsive.

On Tuesday, Atencio's family took him off life support and he died overnight.

Results of a preliminary investigation into why he died are expected in the coming days.

The family of Atencio is exploring a lawsuit against the Maricopa County Sheriff's Office, said Michael Manning, a Phoenix attorney who has won five wrongful-death lawsuits against the department.

Manning said the Gulf War veteran had no brain activity from the moment he arrived at the hospital Friday, did not have alcohol or drugs in his system and had marks from a stun gun on his body.

"At this stage, we all have to give the MCSO the benefit of the doubt, but based on prior experience with these people, I have plenty of doubt," Manning said, adding that the sheriff's office needs to release any surveillance video that may have captured Atencio's scuffle with its officers.

Manning said that in all five of the wrongful-death cases he won against the sheriff's office, video of the incidents had been degraded or destroyed.

Atencio's hospital emergency over the recent week intensified problems for Maricopa Sheriff Joe Arpaio.

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

According to the Arizona Republic, Atencio was arrested by Phoenix police on assault-related charges. Maricopa County sheriff’s officials said 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. 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.

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 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. 

Officials also have 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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