Fighting in Yemen between Houthis and government forces continues to threaten the safety of ships sailing through the Red Sea.
Houthi rebels attacked a Saudi warship with three boats off the western coast of Yemen on Monday, causing an explosion that killed two crew members and injured three others, Saudi state news agency SPA reported.
The incident is yet another reason for alarm, as instability and conflict in Yemen continues to pose a risk to ship sailing through the strategic Red Sea shipping lane which connects the Mediterranean to the Indian Ocean via the Suez Canal.
"A Saudi frigate on patrol west of the port city of Hodeida was hit by a terrorist attack from three suicide boats belonging to the Houthi militias," SPA said.
Houthis carried out a similar attack in October on a vessel being used by the United Arab Emirates military. A Saudi-led force in Yemen had to rescue passengers from the ship.
The conflict between Houthi militias and forces loyal to President Abdrabbuh Mansour Hadi began in 2014. A Saudi-led coalition mounted a military campaign against the rebels in March 2015 as insurgents closed in on Hadi's place of refuge in the southern city of Aden and forced him to seek exile in Riyadh.
Loyalists have since driven rebels out of five southern provinces, including Aden, but the war has ruined Yemen's economy and caused mass food shortages.
Gulf Arab countries say the Houthis are a proxy for their arch-rival Iran, a charge Tehran denies.
International agencies believe at least 10,000 people have died in the mostly stalemated Yemeni conflict, which has unleashed a humanitarian crisis in the impoverished Arabian Peninsula country.