Dar Yasin, Associated Press
FILE — Kashmiri protester shout pro-freedom slogans amid tear gas smoke as they clash with Indian police during a protest after Friday prayers in Srinagar, Indian controlled Kashmir, Friday, Dec. 16, 2016. Nearly 600 people died in Indian police custody from 2009-2015.

NEW DELHI — Nearly 600 people died in Indian police custody from 2009-2015, many of them after being tortured, a human rights group said Monday, urging India to enforce often-ignored regulations and prosecute officers who mistreat prisoners.

Human Rights Watch said police regularly disregard arrest procedures and torture detained people to death. The police often blame such deaths on suicide or illness.

While torture is illegal in the country, many Indian police are open about extracting confessions or details about crimes by applying the "third degree" — a euphemism that can encompass anything from a couple of slaps to a savage beating.

"Until you use third degree against them, they will not speak," said Jairaj Sharma, a retired police officer in India's Uttar Pradesh state.

Citing government data, the report said 97 people died in police custody in 2015. In 67 of those cases, the suspects died within 24 hours of being arrested or authorities failed to take the suspects before a magistrate within 24 hours of arrest, as required by law.

India's Home Ministry did not reply to a request for comment on the report on Monday.

Human Rights Watch said strict enforcement was needed of existing arrest guidelines, such as informing the families of those arrested, providing medical examinations and quickly producing suspects before magistrates.

The New York-based group demanded that police officers who engage in torture and other ill-treatment of prisoners be disciplined and prosecuted.

Police officers will only learn that beating suspects is unacceptable when some are prosecuted, said Meenakshi Ganguly, South Asia director of Human Rights Watch. "Our research shows that too often, the police officers investigating deaths in custody are more concerned about shielding their colleagues than bringing those responsible to justice," she said in an interview.

Vikram Singh, a top retired Indian police officer, acknowledged the country's criminal justice system is riddled with problems, from desperately overcrowded jails to suspects sometimes held for years as cases are investigated. He said police officers have little concern about being punished if they beat a suspect.

"My feeling is that not many cases (against police) have been registered, not many police officers suspended, and certainly no one has been dismissed in recent years for being brutal on accused and wanted criminals," Singh said.

Human Rights Watch focused on 17 of the reported deaths, conducting more than 70 interviews with witnesses, victims' families, justice experts, and police officials.

"In each of the 17 cases, the police did not follow proper arrest procedures, making the suspect more vulnerable to abuse," said Jayshree Bajoria, the author of the report.

In one such case, 37-year-old Shyamu Singh died after being arrested in April 2012 in Uttar Pradesh when police couldn't tell him apart from his older brother Ramu, who was suspected of involvement in a string of extortion and theft cases. When neither brother would give his identity, a group of policemen forced Ramu to the floor.

"Four people held me down and one man poured water in my nose continuously. I couldn't breathe," the report quoted Ramu as saying. "Once they stopped on me, they started on Shyamu."

When Shyamu fell unconscious "they started worrying and talking among themselves that he is going to die. One of the men got a little packet and put the contents in Shyamu's mouth," Ramu said.

Police told their family that Shyamu Singh had killed himself by taking poison.

An initial inquiry by the State Investigation Department concluded in 2014 that seven police officers had tortured Singh and poisoned him to death. But a final inquiry report submitted a year later cleared all seven, according to the report.

AP writer Biswajeet Banerjee contributed to this report from Lucknow, India.