The Indian national who died in an Arizona jail while in the custody of Immigration and Customs Enforcement died by suicide by hanging himself, according to the Maricopa County medical examiner.

Police records also show that Simratpal Singh, 21, had been accused of sexually assaulting a female passenger on a Greyhound bus on April 30, two days before he was found unresponsive and not breathing at the La Paz County Jail in Parker, a rural community in western Arizona near the California border line.

Singh was transferred to ICE custody on May 2 after posting bond on charges of assault and sexual assault. He was being held at the jail while waiting to be transferred to an ICE facility, ICE officials said.

After being found unresponsive, paramedics were called. Singh was taken via ambulance to the La Paz Regional Hospital in Parker and then airlifted to the Abrazo West Campus Hospital, where he was pronounced dead on May 3, according to ICE.

Efforts to revive him were unsuccessful, ICE said.

The Maricopa County Office of the Medical Examiner listed suicide as the manner of death and hanging as the primary cause of death on its website. Autopsy results have not yet been released.

ICE and the La Paz County Sheriff's Office did not immediately respond to a request for comment about the medical examiner's determination that Singh died by suicide.

Singh was arrested on suspicion of assault and sexual assault on April 30 on the westbound Interstate 10 outside of Ehrenberg in far western Arizona near Blythe, Calif., according to police records provided by the La Paz County Sheriff's Office in response to a public records request.

A Greyhound bus driver told sheriff's deputies that a female passenger had accused Singh of sexually assaulting her while she was asleep, the police report said.

The woman said Singh was sitting next to her when she fell asleep. She woke up because Singh was fondling her while she was sleeping, according to the police report.

After Singh was booked into the La Paz County Jail, he told deputies that the woman had placed a blanket over them and then touched him. He said he told the woman to stop but she then showed him a knife, according to the police report. He said he then left his seat and sat in the back of the bus, the police report states.

No passengers witnessed the incident, according to the police report.

Singh was the second person to die in Arizona while in ICE custody in four weeks.

Singh's death comes four weeks after a Mexican national died on April 3 while in ICE custody at the Florence Service Processing Center, an ICE-run detention facility about 60 miles south of Phoenix.

Abel Reyes-Clemente, 54, died after he was placed into medical observation at the Florence detention center on April 1 after showing signs and symptoms of the flu, ICE officials said.

Five people have died in ICE custody since the start of the fiscal year on Oct. 1, according to ICE.

At least 36 people have died while in ICE custody since December 2015, according to a list compiled by the American Immigration Lawyers Association.

Advocates have raised concerns in the past about immigrants killing themselves while in ICE custody.

It is the responsibility of ICE to ensure the safety of immigrants being held in the agency's custody, even when they are being held in a local jail, said Alison Parker, managing director of U.S. programs for Human Rights Watch, an advocacy group.

"We have deep and abiding concerns about ICE's failure to provide adequate medical care to individuals in its custody," Parker said.

A 2018 report by the group Human Rights Watch found that lapses in medical care led to 23 deaths since March 2010. The report independently reviewed 33 of 52 death reports released by ICE since 2010. The report was conducted with the American Civil Liberties Union, National Immigrant Justice Center and the Detention Watch Network.

In addition, the report noted "a troubling pattern of suicides by people with psycho-social disabilities who have been held in isolation."

In deaths involving suicides, Human Rights Watch found officials failed to sufficiently assess the mental health condition of immigrants who died while in ICE custody, or improperly placed them in isolation after mental health issues were noted, Parker said.

Reach the reporter at daniel.gonzalez@arizonarepublic.com or at 602-444-8312. Follow him on Twitter @azdangonzalez. Support local journalism. Subscribe to azcentral.com today.