Government authorities and security forces failed to take action that could have saved hundreds of lives

Human Rights Watch

The official figure put the number of dead below 100.

Human Rights Watch said both Muslims and Christians were to blame for the violence.

But the report said the authorities ignored several warnings from religious and other non-governmental bodies.

Signals

"Government authorities and security forces failed to take action that could have saved hundreds of lives," Human Rights Watch said.

"The Nigerian Government can't just sit back and watch this happen," said HRW official Peter Takirambudde in the report.

"It has a responsibility to maintain peace. There were clear signals that trouble was brewing in Jos but these signals were ignored."

The Nigerian authorities regularly play down casualty figures from religious and ethnic clashes to try to prevent reprisal killings.

President Olusegun Obasanjo ordered the army to restore order after police were overwhelmed by the spreading riots.

Tension

The population of Jos is overwhelmingly Christian, but there is a sizeable Muslim community.

Fulanis and Hausas - two of Nigeria's largest ethnic groups - make up a large proportion of the Muslims.

Relations between Christians and Muslims in northern Nigeria have been tense since the introduction of the Sharia Islamic law in 12 states.

In February 2000, more than 2,000 people were killed in religious unrest in Kaduna, and some 450 more Nigerians died in reprisals in the south-east of the country.

On Tuesday, Gombe became the 13th state to adopt Sharia, when Governor Abubakar Hashidu signed the bill into law.

As elsewhere, he sought to reassure non-Muslims by saying they would still be subject to customary or civil law and only Muslims would be tried under Sharia.