How suicide bombers who planned to disrupt Ethiopia vs Nigeria game blew up themselves

According to a Reuters report, two Somali suicide bombers, whose intention was to kill many football fans during Sunday’s 2014 World Cup play-off between Ethiopia and Nigeria in Addis Ababa, accidentally blew themselves up before they could carry out the attack.
The explosion took place in the Bole district of the country’s capital, which is about 5km from the Addis Ababa Stadium where thousands of fans gathered to watch the game.

“They were Somali nationals and plotted to carry out a suicide attack disguised as fans on either the stadium or areas where large crowds gathered to watch the game,” Ethiopian government spokesman Shimeles Kemal said.
The blast happened one hour before kick-off and explosives, arms, hand grenades and football shirts, were found at the scene. Three suspects have been detained.
Shimeles added: “Heavy police presence must have caused their nervousness and state of agitation which led to the detonation that caused their own death.”
No sect has claimed reponsibility for the incident yet.