The attack happened at 6:30 pm (1530 GMT) Saturday when shells “from across the border with Yemen” hit their patrol, the ministry said in comments carried by the official Saudi Press Agency.
It said the strike occurred in Jazan region’s Harth municipality, where fatal shell fire has landed before.
In coordination with the army, the border guard force “dealt with the situation accordingly,” said the ministry.
The latest casualty brings to at least 31 the number of people, military and civilian, killed in the border area since a Riyadh-led coalition began air strikes against rebels in Yemen on March 26.
Coalition warplanes have been bombing the Iran-backed Shiite Huthi rebels and their allies in support of pro-government forces in Yemen.
The air campaign led to deadly skirmishes between the rebels and Saudi forces along the frontier, and sparked cross-border barrages which have hit residential areas of Saudi Arabia.
Inside Yemen, weeks of fighting between pro- and anti-government forces have killed almost 2,000 people and displaced more than half a million, according to the United Nations. – AFP