Tensions flared in Nigeria today, a day before key national elections, after unidentified gunmen shot dead a hardline Muslim scholar and government critic while he was at prayer in a mosque in the northern city of Kano.

It was not immediately clear if the assassination was linked to tomorrow’s first round of general elections in the vast African country or was the result of a feud between rival sects in the largely Islamic north who have differed bitterly over attempts to impose Sharia law.

Gunmen who burst into the mosque mowed down Sheikh Jafar Adam, a Wahhabi cleric, and two other members of the congregation, police said. Witnesses said the Saudi-educated cleric was shot five times at close range at the Dorayi Central Mosque and died of his wounds before reaching hospital. He was buried today.

The death came as President Olusegun Obasanjo warned the government would “deal firmly” with acts of fraud and violence in the elections. The polls have been dogged for months by bitter infighting and accusations of attempts to organise vote rigging.

Since independence from Britain in 1960, the country has never had a peaceful transition from one elected leader to another. Tensions were already running high with more than 50 political parties vying for hundreds of local and national parliamentary seats and 24 candidates for president.

Sheikh Adam was a prominent member of Sunni Islam’s strict “Wahhabi” sect in Nigeria, which had accused the Kano state authorities of failing to implement Islamic law properly.

Kano is one of 12 northern Nigerian states, which introduced Sharia in 2000, a move by state governors that alienated the Christian minorities and sparked violence. Southern Nigeria is predominantly Christian and traditionally the presidency is swapped between the two regions.

Voters will tomorrow choose 36 new governors, key positions in federal Nigeria. The following Saturday, they will return to the polls to elect a new president.

President Obasanjo, who has to stand down after two terms, is accused of manipulating the ruling party machine to put a compliant ally in the job. The governorship elections will give an indication of whether the ruling People’s Democratic Party can win a new presidential term.

In a national radio and TV broadcast, Mr Obasanjo ominously accused “highly placed individuals” of encouraging violence in the country. His remarks were interpreted as an attack on Vice-President Atiku Abubakar, who has fallen out with the president and has been barred from standing.

Meanwhile, a police officer and four other people were killed in gang violence in the oil-rich Delta region.

Last month, gunmen killed four police officers in Port Harcourt, the state capital and centre of Nigeria’s oil industry. For months, the Delta has been plagued by attacks by militant groups who are demanding a greater share of Nigeria’s oil revenue and have kidnapped scores of local and international oil workers.

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