Amnesty International's delegation
has documented many cases of abuse including killings following excessive use of force, arbitrary arrests of
demonstrators by security forces and indiscriminate, unnecessary
use of tear gas.
Santiago Omar Riveros, who ran a detention centre, was found guilty of torturing and beating to
death a 15 year old boy. He is also accused of over 40 crimes against humanity involving victims of the era's so-called "disappeared".