According to County commissioner Fredrick Shisia, the number of those injured in the Morning attack has not yet been confirmed.
One bus managed to speed off after it was shot at while travelling between Elwak and Wargadud area while the second stalled after it hit by bullets from the militants.
Among those killed is a Kenya Police Reservist who was escorting the bus. His colleague was injured in the attack.
Mr Shisha confirmed that Police had already launched an operation in the area to track down the attackers.