Nigeria raced into a 4-0 lead inside the first half-hour as Alex Iwobi scored twice, the first in the fourth minute, and Victor Osimhen and Samuel Chukwueze added two more.
But Kwame Quee pulled one back for Sierra Leone four minutes before the break after which the visitors staged a remarkable recovery with Alhaji Kamara scoring twice in between Mustapha Bundu’s effort – all in the final 18 minutes – to draw.
Angry fans demonstrated outside the stadium after the game forcing Nigeria’s team to spend several hours in their changing room before being able to leave.
Nigeria remain top of Group L with seven points from three games while Sierra Leone moved off the bottom on two.