SANAA, Yemen—Security officials say an explosion has struck a military bus in the Yemeni capital, killing at least two troops.

The officials say the Tuesday morning blast in Sanaa also wounded at least 10 soldiers. It hit as the bus was passing through the Dar Silm district, taking officers and troops to work.

The officials say they are investigating whether the explosion was caused by a bomb hidden on the bus, a roadside device or a suicide bomber. They spoke on condition of anonymity according to regulations.

Yemen, the Arab world's poorest country, is plagued by an al-Qaida insurgency and has seen scores of attacks on its military or security forces.

In August, a bomb hidden on a bus carrying air force personnel in Sanaa killed three people and wounded 23.