Unidentified gunmen shot dead a colonel of Yemen's military intelligence agency in the southeastern province of Shabwa on Saturday evening, a government official told Xinhua.

About two masked gunmen on motorcycles fired four times at Colonel Ahmed Hashim in Shabwa's provincial capital of Ataq, killing him on the spot, before fleeing the scene, the local source said on condition of anonymity.

A local resident confirmed to Xinhua saying that "the officer was driving toward his home when targeted by armed men. Police subsequently sealed off the street and deployed forces in the area. "

Colonel Hashim is the latest victim of a series of drive-by killings that mainly target intelligence and army officers in the country's restive south.

The local authorities have launched an investigation into the incident, the source said, adding that the killing was probably committed by terrorists of the al-Qaida group.

The al-Qaida in the Arabian Peninsula, emerged in January 2009, is considered the most strategic threat to the Yemeni government and neighboring oil-rich Saudi Arabia.