While Azzam drove the Toyota Dyna quickly toward the Nairobi embassy along with Mohamed Rashed Daoud Al-Owhali, local security guard Benson Okuku Bwaku was warned to open the gate immediately – and fired upon when he refused to comply. Al-Owhali threw a stun grenade at embassy guards before exiting the vehicle and running off. Osama bin Laden later offered the explanation that it had been Al-Owhali's intention to leap out and shoot the guards to clear a path for the truck, but that he had left his pistol in the truck and subsequently ran off. As Bwaku radioed to Marine Post One for backup, the truck detonated.