A U.S.-based human rights organization has sharply criticized the Islamic law court system in northern Nigeria, citing discrimination and the use of confessions extracted by torture.

Human Rights Watch is calling on the Nigerian government to stop what it calls human rights abuses and constitutional violations taking place in the Islamic law courts. Among the abuses cited in their report, the group says many people sentenced to amputation have been convicted on confessions extracted under torture by the police.

The report claims the Islamic court system is politically motivated and does not offer representation to defendants or inform them of their rights.

Officials in Nigerian states practicing Sharia have dismissed the report. One official in Zamfara state told the Associated Press no amount of criticism will make them change the system.

Islamic or Sharia law was reintroduced in Nigeria in January 2000 when the governor of Zamfara state signed a decree that says all Muslim citizens of the state are to be tried in Islamic courts. Eleven other states followed suit, but trials under Sharia law are not mandatory in all of the states.

A spokeswoman for Human Rights Watch, Carina Tertsakian, says they are mainly concerned with the cruel and unusual punishments used by the courts.

"We are particularly concerned about those sentenced to amputations," she noted. "So far, only two or three have actually had their hands amputated but many others are currently still in prison with this amputation sentence hanging over them and not knowing what is going to happen. The majority of them confessed on the basis of statements extracted under torture and those confessions were the basis for the conviction."

Ms. Tertsakian says amputation is not a sentence that would be rendered in the common law system, which operates in the rest of Nigeria. She also says that women are discriminated against in the Islamic law courts.

"Women have been and still are discriminated against both in the legislation, but also in practice," she added. " Regarding the legislation, this is particularly apparent in cases of adultery or extramarital sex where the standards of evidence are different for men and for women. So, for example, if a woman is pregnant that is considered sufficient evidence to convict her of adultery. Whereas for the man, they need to have four independent eyewitnesses to the act, which you can imagine is practically impossible to obtain and therefore in several cases the men have been acquitted."

In many adultery cases in Nigeria, the accused women have been raped and due to a lack of witnesses to the crime they are found guilty. The punishment for adultery is flogging or stoning to death. Human Rights Watch is urging the international community to condemn the unfair practices in Nigeria.