In a report released on Monday, US-based Human Rights Watch (HRW) said that 591 people died in police custody between 2010 and 2015, mainly due to torture and ill-treatment of prisoners.

The 114-page report draws on "in depth investigations" into 17 deaths in custody, including over 70 interviews with victims' family members, witnesses, legal experts and police officers. The report also found that police blamed the deaths on suicide, illness or accidents.

According to the report, in most cases, the police failed to follow arrest procedures, such as presenting a suspect before a magistrate within 24 hours, which allowed them to get away with murder.

"Since these deaths are not happening in an open domain, it is very hard to prove how they died if the other police officials who are witnesses shield their colleagues," Jayshree Bajoria, author of the report, told the AFP news agency.

"The lack of accountability of police is the reason why there is continued impunity for custodial deaths in India," she said.

In a case cited in the report, Shyamu Singh, a prisoner, died in police custody on April 15, 2012, in the northern state of Uttar Pradesh. Police claimed that Singh had committed suicide, but his brother, who was also arrested with Singh, said that after their arrest they were tortured by police.

'Unfortunate'

Vrinda Grover, a New Delhi-based lawyer and human rights activist, told DW that he was not surprised by the findings of the report.

"Torture and fake encounters happen regularly in India. This is a blot on India's civil rights record and we won't see a change until the authorities take an action to stop these practices," said Grover.

HRW examines the reasons behind custodial deaths in India and recommends measures that authorities can and should take to end the practice.

The rights organization also found the number of deaths was higher in the states of Uttar Pradesh, West Bengal, Maharashtra and Tamil Nadu.

Police reforms

The scathing indictment on the role of Indian police has only confirmed what the country's rights activists and lawyers have been pointing out for many years. Indian human rights organizations have demanded urgent police reforms in the light of the HRW report.

"The figures quoted in the HRW report are accurate. It is unfortunate that the government has never acted against those responsible for these deaths," Harish Dhawan of the Peoples Union for Democratic Rights told DW.

Dhawan said that police officials always justify the use of torture as a means of interrogation.

"In most cases, the police torture poor citizens, who cannot protect themselves," added Dhawan.

HRW's report endorses this claim: "Many of these families are poor and socially marginalized, making them especially vulnerable to such harassment."

The officials declined to comment on the report when contacted by DW.

The government's findings also say that as many as 1,275 people died in police custody between 2001 and 2013. But only 26 police officers have been convicted for these deaths in over a decade.