Amateur video shows Indian police beating a suspect
Police in India are guilty of widespread human rights violations, including beatings, torture and illegal killings, a new report alleges.
The US-based group Human Rights Watch says India's policing system facilitates and even encourages abuses.
It says there has been little change in attitudes, training or equipment since the police was formed in colonial times with the aim to control the population.
It says the government must take major steps to overhaul a failing system.
There was no immediate response from the Indian authorities.
The BBC's Damian Grammaticas in Delhi says the catalogue of abuses by India's police detailed in this report is long and shocking - arbitrary arrests, beatings and torture to force confessions, even the cold-blooded gunning down of innocent people.
The police are often a law unto themselves, say campaigners
"[M]y hands and legs were tied; a wooden stick was passed through my legs. They started beating me badly on the legs with lathis [batons] and kicking me," the report quoted a fruit vendor in the city of Varanasi as saying.
"They beat me until I was crying and shouting for help. When I was almost fainting, they stopped the beating... Then they turned me upside down... They poured water from a plastic jug into my mouth and nose, and I fainted," he said.
Human Rights Watch spent a year investigating claims of human rights violations to compile the 118-page report, entitled "Broken System: Dysfunction, Abuse and Impunity in the Indian Police".
It says the report is based on interviews with more than 80 police officers of varying ranks, 60 victims of police abuses and numerous discussions with experts and civil society activists.
The report says that "abysmal conditions for police officers contribute to violations".
Human Rights Watch says it spoke to 80 police officers
Ill-equipped and under pressure to fight crime, police officers often take the law into their own hands, it says.
"Low-ranking officers often work in difficult conditions. They are required to be on-call 24 hours a day, every day. Instead of shifts, many work long hours, sometimes living in tents or filthy barracks at the police station.
"Many are separated from their families for long stretches of time. They often lack necessary equipment, including vehicles, mobile phones, investigative tools and even paper on which to record complaints and make notes."
Human Rights Watch says that as India has modernised fast, its police have been left behind.
"India is modernising rapidly, but the police continue to use their old methods: abuse and threats," said Brad Adams, Asia director at Human Rights Watch.
"It's time for the government to stop talking about reform and fix the system."
The authorities require a major overhaul - otherwise the beatings, torture and illegal killings will continue to stain India's democracy, the report adds.
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