A gunman killed two Yemeni workers for the International Committee of the Red Cross on Wednesday, a spokesperson for the aid group said, the latest in a series of incidents to hit the organization’s operations in the conflict-ridden Gulf country.

The attacker opened fire on two cars marked with ICRC insignia as they drove from northern Saada province to the capital, San’a, said Rima Kamal, the group’s spokeswoman in Yemen.

The identity of the gunman was not immediately known.

Both workers were Yemeni nationals working with the Geneva-based organization’s local office. One died at the scene, and the second died after being taken to the hospital, Ms. Kamal said. Their names were not released.

"It is seemingly a deliberate targeting," she said. "We are very shocked, appalled and saddened."

Last month, the ICRC, which operates across Yemen, closed its office in the southern port city of Aden after unknown gunmen stormed the building and held staff at gunpoint.

The workers were unharmed, but the gunmen stole cars, cash and laptops.

A Saudi Arabia-led coalition has carried out airstrikes against Iran-backed Houthi militants in Yemen since March. It recently began deploying troops on the ground,alongside soldiers from the United Arab Emirates.

The air campaign began after the rebels took control of San’a, forcing President AbedRabbo Mansour Hadi into exile in Riyadh, Saudi Arabia.