Amnesty International has accused Kazakhstan's president of concealing evidence of torture and the use of excessive lethal force by police.
In a report released on July 11, the London-based rights monitoring group called on Nursultan Nazarbaev to allow an independent international investigation into the violent dispersal of protesting oil workers in western town of Zhanaozen in December 2011.
The report says least 15 protesters were shot dead by police there, about 100 were wounded, and many were detained and tortured in custody.
It also highlights the treatment of jailed dissident poet Aron Atabek, who has already spent 2 1/2 years in solitary confinement under what was described as "very harsh, unhealthy conditions."
Amnesty International called on Nazarbaev to keep his 2010 promise to the United Nations to totally eliminate all vestiges of torture.
The report is titled "Old Habits: The Routine Use of Torture and Other Ill-Treatment in Kazakhstan."