PM Abiy Ahmed was whisked away by guards at the event attended by thousands in Addis Ababa.
The head of Kenya's national consumer protection agency is among 10 senior government officials being detained.
Ahmed Musa scores both goals as Nigeria beat World Cup debutants Iceland to leave Group D intriguingly poised.
Broadcast time 07:06 BST - 08:00 BST
Broadcast time 08:06 BST - 08:30 BST
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Broadcast time 11:06 BST - 11:30 BST
12 Russian foods to enjoy during the World Cup
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