The United Nations Children's Fund UNICEF said Friday that 240 villages have reportedly been evacuated and more than 50 schools closed in Saudi Arabia after the conflict in North Yemen spilled over the border.
Thousands of Saudis are huddling in tent cities after having to abandon their homes when fighting between Yemeni troops and Shiite rebels spilled across the border.
"UNICEF is deeply concerned about the escalation of the conflict in northern Yemen," said UNICEF regional director for the Middle East Sigrid Kaag.
"Fighting has now spilled over into Saudi Arabia, reportedly causing 240 villages to be evacuated and more than 50 schools to be closed," she added in a statement received in Geneva.
Saudi Arabia said on Tuesday that it would keep up air strikes against Yemeni rebels until they pull back from its border.
Shiite Zaidi rebels said Saudi warplanes had continued to strike them, a week after a rebel raid into Saudi territory sparked air and ground bombardment of their positions.
Saudi forces entered the fray on Nov. 4, pounding rebel positions on the 2,000-meter Jebel al-Dukhan mountain straddling the border, after rebels killed a border guard and occupied two Saudi villages.
It was the first overt action by Saudi forces against the rebels, also known as Houthis, since Yemeni forces launched "Operation Scorched Earth" against the insurgents on Aug. 11.
UNICEF said the number of displaced to al-Mazraq camp in northern Yemen's Hajjah governorate has more than doubled in four weeks to 15,000, while 28,000 more people who fled fighting were living outside the camp.
"The total number of people displaced by the conflict has gone up to more than 175,000, from an estimated 150,000 only a few weeks ago," added Kaag, while malnutrition was reaching "alarming levels" in Yemen.
Fighting between Yemen forces and rebels first broke out in 2004, and Yemeni President Ali Abdullah Saleh has pledged to crush the rebellion.
Saudi Deputy Defense Minister Prince Khaled bin Sultan said on Tuesday his country will keep up air strikes against the rebels until they pull back from the border.