Witnesses reported that people in a moving car hurled three grenades at the outdoor terminal, police spokesman Charles Owino said. Government minister Esther Murugi, who spoke after visiting Nairobi's main hospital where the wounded were brought, said six needed emergency surgery. Earlier, a Red Cross official said 12 people were in critical condition.
The blasts are the latest in a string of small arms, bomb and grenade attacks that have killed scores of people since Kenya sent troops across the border into neighboring Somalia in October. The incursion followed a string of attacks by Somali gunmen on Kenyan soil. Somalia's al-Qaida-linked insurgency vowed revenge and incited sympathizers to carry out attacks in Kenya.
"The more you attack us, the more we will become aggressive," Owino said.
Witness Ruben Otsembo was filling up his motorcycle at a nearby gas station when a man covered in blood ran up shouting about an explosion and bodies, and then collapsed and died in front of him. Another man, who was wounded in the arms and legs while he was buying a bus ticket, said he heard two explosions.
"It was the second one that got me," said Frederick Shikutu, 36, as he was being loaded into an ambulance.