RIYADH, Saudi Arabia (AP) — Attacks by Yemeni rebels have killed three Saudi soldiers and wounded another three along the border, the Saudi military said Tuesday.

The official Saudi Press Agency said two soldiers were killed in action on Tuesday. Another was killed Monday when the rebels, known as Houthis, attacked a border post in the Jizan province with rocket and artillery fire. The statement said Saudi troops fired back, without providing further details.

Saudi Maj. Gen. Abdulrahman al-Shahrani was killed Sunday in the same region. He is the highest-ranking Saudi officer to be killed in the conflict since March, when a Saudi-led coalition began launching airstrikes against the Iran-supported rebels. Several dozen Saudi soldiers have been killed in border attacks since the airstrikes began.

Yemen's conflict pits the Houthis and troops loyal to a former president against an array of forces including southern separatists, local and tribal militias, Sunni Islamic militants as well as troops loyal to President Abed Rabbo Mansour Hadi, who is in Saudi Arabia.

Iran's Deputy Foreign Minister Hossein Amir Abdollahian said Tuesday that Saudi Arabia's continuation of the war in Yemen "risks spreading the crisis, and especially increasing the growth of terrorism."

He added, however, that Iran was ready to cooperate with Riyadh on the matter, Iran's official IRNA news agency reported.

The International Committee of the Red Cross meanwhile withdrew its 14 foreign staffers from Aden following an attack by masked gunmen who held employees at gunpoint and made off with cash, cars and equipment. Pro-government forces recently drove the Houthis out of the southern port city.

ICRC official Samer Jarjouhi said the Red Cross office had faced "at least 10 such incidents recently."