Human Rights Watch called on Indian authorities to prevent wrongful accusations of terrorism, investigate allegations of coerced confessions of terror suspects, and hold to account those responsible for torture.
"State police, jail officials, and other authorities have committed a range of human rights violations, including arbitrary arrest and detention, torture, and religious discrimination," the New York-based group said in a 106-page report released Wednesday.
India's Home Ministry said it would not be commenting on the report.
The ministry "does not react to comments made by human rights groups," Onkar Kedia, a home ministry spokesman, said Wednesday.
The report describes mistreatment, including torture, of alleged members of the Indian Mujaheddin, a banned Muslim terrorist group, that has claimed responsibility for at least six deadly terror attacks since 2008.
"Indian police are under tremendous pressure to identify the perpetrators of horrific attacks, but they need to do so without resorting to the use of arbitrary arrests and torture to coerce confessions," said Meenakshi Ganguly, South Asia director at Human Rights Watch.
At least 152 people died in three bombings in major Indian cities in 2008, after which scores of Muslims were detained as suspects, beaten, blindfolded and shackled, the report said.
The rights group has called on Indian authorities to impartially investigate the case of nine Muslims held as suspects and tortured for a series of bomb attacks in 2006 in Malegaon in the western Indian state of Maharashtra and in two other cities. Further investigations revealed the lead suspects were Hindu extremists.
However, nine Muslim men were still being held for the Malegaon blasts, the report said.
The rights group has called for a repeal of the unlawful provisions of India's counterterrorism laws, including long detentions, arbitrary arrests and all forms of torture to secure "confessions" from terror suspects.
Human Rights Watch has called for investigations into wrongdoing by police and other officials, including the accusations of alleged Indian Mujahideen suspects and Muslims previously rounded up in attacks now blamed on Hindu extremists, and an end to the culture of impunity for crimes against terrorism suspects and others in India.