Some staff attached to the first lady have been taken into custody by the police.
The incident happened last week but the news emerged at the weekend with both President Buhari and his wife making statements.
Mr Buhari says armed guards and other security personnel assigned to the presidency were given the necessary training especially in weapons handling and “where they come short, their relevant agencies have their rules and regulations to immediately address them”.
A government statement says that the president ‘’is not, and was not at anytime in any form of danger arising, either from deadly infections or the reported incident by security personnel which is currently under investigation”.
A statement issued by Mr Buhari’s spokesperson, Garba Shehu, said the “minor” incident happened outside the main residence of the president.
Earlier, in a tweet, First Lady Aisha Buhari called on the chief of police to release her staff ‘’in order to avoid putting their lives in danger or exposure to Covid-19 while in their custody”.