*Updates with confirmed age

Abba Kyari, the trusted chief of staff to Nigeria’s president Muhammadu Buhari, has died from complications related to Covid-19 after a nearly month-long battle with the virus.

Kyari had widely been seen as one of the three most powerful people in Africa’s largest economy and said to have the complete trust of Buhari. Some had even described him as the de facto head of the government because in a country where the presidency holds an inordinate amount of centralized power and government funds, deciding who has access to the president accords immense power and influence.

And even with a political culture overweighted in outsized egos, Nigeria’s government ministers and state governors had to learn to work by going through Kyari before getting to the ultimate “oga”.

Despite his high profile role, the late chief of staff has not been one for the political limelight. There are few official public photographs of him and even his official age was not readily available in the early obituaries, though a tweet on Saturday from president Buhari confirmed he was 67.

Kyari, who graduated from Cambridge and Warwick universities in the United Kingdom in the early 1980s, was often described as an intellectual by those who dealt with him.

The late chief of staff was said to have contracted the coronavirus on an official trip to Germany in March. He was confirmed with the virus on Mar. 23. At the time, he was said to be in high spirits and widely expected to recover. But there have now been reports Kyari had underlying conditions.

Kyari’s passing is a major blow to the Buhari presidency. It leaves a gaping hole in the administration as it juggles responding to a coronavirus outbreak—which is likely to tip Nigeria’s economy into its worst recession in 30 years according to the IMF—and battling multiple insecurity challenges, including a devastating Boko Haram insurgency that has left the military stretched. Kyari’s passing may also force president Buhari into a quick shake-up of his cabinet—a reality which flies in the face of the president’s preference for slow-paced decision making.

Kyari was one of several high profile political figures in Nigeria to have contracted the virus. The state governors of Bauchi (Bala Mohammed) and Oyo (Seyi Makinde) both contracted the virus in March and have recovered. The Kaduna governor Nasir El-Rufai is still in care.

Nigeria still has a relatively low number of confirmed coronavirus cases with just 493 and 17 deaths, relative to its 200 million population. But there have been significant concerns the country is not giving enough tests to be certain with around just 7,000 tests done.

Additional reporting by Yomi Kazeem in Lagos

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