SANAA, Yemen — Gunmen in Yemen opened fire on the car of a Saudi Arabian army officer working with his embassy's military section on Wednesday, killing him and his Yemeni bodyguard, officials from both countries said.

Yemeni officials said the Saudi officer, who had diplomatic status, was traveling to the embassy when he was shot by gunmen wearing army uniforms in another car. The officials spoke on condition of anonymity because they were not authorized to brief reporters.

Saudi Arabia maintains close ties with Yemen, the poorest country in the Arab world and home to an al-Qaida branch considered to be the terror network's most dangerous. The militant group is active on the Yemeni side of the two countries' border, and has drawn Saudi nationals into its ranks there.

Saudi Arabia's official news agency confirmed the attack and said an investigation had been launched. The Saudi officer was part of the security detail for the military attaché to Yemen, it said, adding that the gunmen who attacked him were wearing uniforms of the "central security forces".

Last year, Saudi officials played a key role in a U.S.-backed deal that saw President Ali Abdullah Saleh step down and transfer power to his vice president.

Islamic militants took advantage of Yemen's popular uprising last year to seize parts of the country's south. Last summer, backed by U.S. advisers and drones, the Yemeni military reclaimed much of the area, driving militants from a series of strongholds.

The militants have in turn struck back, targeting security officials for assassinations.