Niger Leader Dies; Cousin Takes Power : Kountche Became Ruler of West African Nation in 1974 Coup

President Seyni Kountche, who seized power 13 years ago from a corrupt civilian regime, died Tuesday in Paris.

His cousin, Col. Ali Seibou, the army chief of staff, was named acting president of Niger.

Seibou announced the death in a communique read on state-controlled Niger radio but gave no cause. It is believed that Kountche, 56, suffered from a brain tumor.

The radio said Tuesday morning that Seibou, 47, took control because of Kountche’s poor health. It said the decision of the ruling Supreme Military Council will be in effect “until further notice.”

Later broadcasts placed Kountche’s time of death in a Paris hospital at two hours after his ouster.

Month of Mourning

Seibou called on his countrymen to remain calm and said the army will continue to assure the country’s security. The country will observe a month of mourning, the radio said.

Kountche, a major general when he died, came to power in a 1974 military coup, promising to end widespread corruption and improve distribution of food aid in this poor West African nation. He had been in poor health since last January and had flown to France at least five times for medical care.

French President Francois Mitterrand called Kountche “one of the most remarkable heads of state of black Africa.” Niger was part of France’s colonial empire from 1883 to 1960.

Seibou, an adviser to Kountche, had held the post of chief of staff since the coup. Western diplomats said Seibou had long been considered the prime candidate to replace Kountche.

Kountche seized power at the height of a five-year drought that had devastated Niger’s agriculture. He deposed civilian President Hamani Diori, who had ruled Niger since independence from France.

Diori’s regime was characterized by political instability and corruption, including the alleged hoarding of much-needed food aid by some of his ministers.

After Kountche took over, Niger rebounded and experienced a brief economic boom in the 1970s when production of uranium, Niger’s main mineral resource, was up and prices were good.

Then, a second wave of drought in 1984-85 wiped out many of the gains that had accumulated through the last decade.

However, Kountche’s successes in leading the country toward self-sufficiency in food--which included an austerity program--minimized the effects of the drought.

A devout Muslim who placed strong emphasis on morality and discipline, he achieved his goals with some ruthlessness, sound economic planning and with help from the International Monetary Fund.

He survived at least two coup attempts, the last in 1983. Police maintained a high profile, and travel outside the capital usually required permits.