Updated

Yemeni security officials say suspected al-Qaida militants have killed a security officer in a drive-by shooting in the capital, Sanaa.

The officials say the attackers opened fire from a car in downtown Sanaa on Monday morning and killed officer Mohammed Qawza of the Defense Ministry's linguistics institute. The assailants fled the scene of the shooting.

The officials say that also on Monday, a roadside bomb targeted a military bus in Sanaa's Old City and wounded two passers-by. The officials spoke on condition of anonymity in line with regulations.

The U.S.-backed Yemeni army has been trying to defeat al-Qaida's local branch, considered the terror network's most active.

Hundreds of journalists, writers, poets and others rallied in Sanaa on Monday in support for the army's campaigns against al-Qaida.