Former Nigerian president Shehu Shagari, who was in power between 1979 and 1983, died on Friday aged 93, the country's current president said."On behalf of my family, the government and the people of Nigeria, it is with immense sadness that I received the news of the passing away of the First Executive President of Nigeria, Alhaji Shehu Shagari" in the capital Abuja, President Muhammadu Buhari said in a statement.Buhari, a former general, led a bloodless coup against Shagari's government in 1983."Nigerians held him in the highest esteem even when he was out of office until his demise and will forever miss his wise counsels," the president added in his statement. Shagari, a Fulani Muslim from Nigeria's northwest, became the country's first executive president with full, rather than ceremonial, powers when the country introduced a US-style system in 1979.Under his rule, the state of the economy deteriorated as oil prices fell in the early 1980s, mismanagement increased and debt piled up.Despite these woes, Shagari won what was described by his party as a "landslide victory" in 1983. But the vote was bitterly contested by the opposition, with allegations of electoral fraud.On December 31 that year, Buhari toppled the government and Shagari was arrested with many of his ministers and notable party members on corruption charges.After a series of military-backed trials, the deposed leader was cleared of graft allegations.Since leaving politics, Shagari largely retired from the public eye.* Sign up to News24's top Africa news in your inbox: SUBSCRIBE TO THE HELLO AFRICA NEWSLETTERFOLLOW News24 Africa on Twitter and Facebook.