Nigeria president attends Friday prayers amid health woes

In this photo released by the Nigeria State House, Nigeria's President Muhammadu Buhari, centre, with government officials after Friday prayers at the presidential palace in Abuja, Nigeria, Friday, May. 5, 2017. Nigeria's 74-year old president has emerged to attend Friday prayers after missing a number of public engagements and three straight weekly cabinet meetings because of poor health. (Sunday Aghaeze/Nigeria State House via AP) (The Associated Press)

In this photo released by the Nigeria State House, Nigeria's President Muhammadu Buhari, centre, greets government officials after Friday prayers at the presidential palace in Abuja, Nigeria, Friday, May 5, 2017. Nigeria's 74-year old president has emerged to attend Friday prayers after missing a number of public engagements and three straight weekly cabinet meetings because of poor health. (Sunday Aghaeze/Nigeria State House via AP) (The Associated Press)

In this photo released by the Nigeria State House, Nigeria's President Muhammadu Buhari, centre, arrives for Friday prayers at the presidential palace in Abuja, Nigeria, Friday, May. 5, 2017. Nigeria's 74-year old president has emerged to attend Friday prayers after missing a number of public engagements and three straight weekly cabinet meetings because of poor health. (Sunday Aghaeze/Nigeria State House via AP) (The Associated Press)

Nigeria's president has emerged to attend Friday prayers after missing a number of public engagements because of poor health.

President Muhammadu Buhari disappeared for six weeks of medical leave in London earlier this year, leading some to call for his replacement. The 74-year-old returned to work in March but has missed three straight weekly cabinet meetings.

The uncertainty over his health has raised fears of instability in Africa's most populous nation and one of its top oil producers.

Nigeria's government tweeted images of Buhari's appearance Friday as officials seek to calm the concerns.

Buhari's ailment is not publicly known, but he has made reference to blood transfusions and said he had not been so sick in decades.

His wife has said his health is not as bad as perceived.