Both of the bombs exploded northeast of Nairobi on the Thika Road and detonated 1 kilometre ( 0.62 mi ) apart .
The Thika Road is an eight - lane controlled - access highway .
Both of the bombs exploded northeast of Nairobi on the Thika Road , an eight - lane controlled - access highway , and detonated 1 kilometre ( 0.62 mi ) apart .