A Nigerian civil rights group said Wednesday it would appeal an Islamic court order to shut down its chat forums on Facebook and Twitter which criticize the practice of Islamic law in northern states.

An Islamic court in the northern city of Kaduna Monday ruled for the Association of the Muslim Brotherhood of Nigeria, which sought to censor debate on the social networking sites over an amputation case that occurred 10 years ago.

The Civil Rights Congress began the debate on Facebook and Twitter last week, asking members their opinions over the amputation of a peasant farmer's hand in March 2000 after he was convicted by an Islamic court for stealing a cow.

Shehu Sani, the group's president, said he started the discussion to highlight what he believes is the unfair practice of sharia law by Nigeria's northern states.

Sharia law seems to only apply to the poor and downtrodden. It is wrong that this farmer's hand was amputated, while politicians steal hundreds of millions of dollars without being punished, he said.

The rights group is expected to appeal the ruling to an upper sharia court Monday.

We condemn the ruling and reject it. We think it is a violation of our freedom of expression, Sani said.

Africa's most populous nation is roughly equally divided between a mainly Muslim north and largely Christian south.

More than 200 ethnic groups generally live peacefully side by side but there have been regular outbreaks of violence, particularly in the Middle Belt separating the north and south, where sectarian clashes have killed hundreds this year. Islamic jurisprudence in Nigeria is based on the moderate Maliki school of Sunni Islam.

The enforcement of sharia law in 12 of Nigeria's 36 states in 2000 alienated sizeable Christian minorities in the north and sparked clashes which killed thousands.

(Editing by Nick Tattersall and Jon Hemming)

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