India is failing to protect its lower castes who are routinely attacked and shunned because of their social status
New York-based Human Rights Watch said more than 165 million Dalits -- once known as untouchables -- were "condemned to a lifetime of abuse simply because of their caste".
"Dalits endure segregation in housing, schools, and access to public services," the report titled "Hidden Apartheid: Caste Discrimination against India's Untouchables" said.
"They are denied access to land, forced to work in degrading conditions and routinely abused at the hands of the police and upper-caste community members who enjoy the state's protection."
Dalits make up around 160 million of mainly Hindu India's 1.1-billion population. Despite efforts to tackle prejudice, the age-old caste hierarchy still divides society.
Last week, an official commission found India's police and legal system had failed "deplorably" to protect those at the bottom of the social ladder and suggested exclusive courts be set up to ensure speedy justice.
Tuesday's report was prepared with the help of the Center for Human Rights and Global Justice at New York University.
It said caste-motivated killings and rapes were a daily occurrence in India, and that 58,000 cases were registered between 2001 and 2002 under legislation designed to protect lower castes and tribal groups.
Human Rights Watch said 2005 government figures suggested a crime was committed against a Dalit every 20 minutes.
"International scrutiny is growing and with it the condemnation of abuses resulting from the caste system and the government's failure to protect dalits," said Brad Adams, the group's Asia director.
"India needs to mobilise the entire government and make good on its paper commitments to end caste abuses. Otherwise, it risks pariah status for its homegrown brand of apartheid."
The report detailed specific instances of abuse. It said Dalits were still forced to perform jobs considered too "polluting" for others -- 1.3 million dalits, mostly women, were employed to remove human waste from pit latrines manually.
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