Shellfire from Yemen killed one civilian and a member of the security forces in Saudi Arabia on Tuesday, officials said.
The latest casualties bring to at least 28 the number of people, military and civilian, killed in the Saudi border zone since a Saudi-led coalition began air strikes against Iran-backed Shiite Houthi rebels in Yemen on March 26.
The civilian died and five more were wounded at about midday when incoming fire hit Najran city, the civil defence department said, quoted by the official Saudi Press Agency.
It said the wounded were taken to hospital.
Also in Najran, the security officer died and three others were hospitalised earlier Tuesday when "military missiles from inside Yemen" hit their location, the interior ministry said.
Saudi-led coalition warplanes have been bombing Houthis in support of pro-government forces in Yemen.
The air campaign led to deadly skirmishes between the rebels and Saudi forces along the border, but many of the recent Saudi casualties have been civilians killed by cross-border barrages.
Inside Yemen, weeks of war between pro- and anti-government forces have killed almost 2,000 people and displaced more than half a million, according to the United Nations.