The discovery of nine slain members of the ethnic Hausa group in a neighborhood dominated by their Yoruba rivals may be a sign of deepening ethnic strife following the death of Nigeria's most prominent political prisoner.

Police found the remains separately in the past day in a predominantly Yoruba neighborhood in southern Lagos, Nigeria's commercial capital.A senior police commander in the capital described many of the youths who rampaged for the third straight day as jobless, disenfranchised Yorubas. The rioters set fires, smashed windows and blocked roads in Lagos.

The violence began after Tuesday's death of Moshood Abiola - a Yoruba and the apparent winner of annulled presidential elections in 1993. His supporters say the northern- and Hausa-dominated military is to blame.

Riot police and paramilitary troops have been ordered to protect mosques, which could become targets for attacks by the predominantly Christian and animist southerners.

More than 400 people have been arrested since Tuesday night, when violence first broke out in the capital, police say. At least 24 people have been killed.

Abiola, imprisoned for the past four years, died Tuesday in the custody of his military captors while meeting with U.S. officials.

The army says he died of a heart attack, but some of Abiola's relatives say he was killed by the military even as they prepared to set him free.

The ruling junta says it has completed an autopsy, but hasn't released the results. A second, independent autopsy to be conducted by a team of foreign pathologists, was expected today.

Many of those killed in the violence following Abiola's death were members of the Hausa and related Fulani groups, said military junta commander Col. Hamed Ali.

"Counsel your subjects on the need for peaceful coexistence," Ali told a joint meeting of Yoruba, Hausa and Ibo elders in Lagos late Thursday.