President Muhammadu Buhari’s chief of staff, Abba Kyari, has died after contracting the Covid-19 coronavirus.

Abba Kyari was the top official aide to Muhammadu Buhari and one of the most powerful men in Nigeria. Like Buhari, he was in his 70s, and he had underlying health conditions, including diabetes.

Presidential spokespeople confirmed Kyari’s death on Twitter:

“The Presidency regrets to announce the passage of the Chief of Staff to the President, Mallam Abba Kyari.

“The deceased had tested positive to the ravaging COVID-19, and had been receiving treatment. But he died on Friday, April 17, 2020.

“May God accept his soul.”

Kyari tested positive for coronavirus in late March after visiting Germany, forcing a string of top Nigerian officials who had been in contact with him to self-quarantine.

In a statement released on March 29, Kyari said he had been transferred to Lagos, Nigeria’s biggest city, for private medical treatment and hoped “to be back at my desk very soon”.

There has been no official confirmation on whether Buhari has taken a test, but the president has since made repeated televised speeches imposing restrictions to curb the spread the virus.

Kyari is the highest-profile COVID-19 death in Nigeria which has 493 confirmed cases and 17 deaths.