Two Saudi pilots died when their Apache helicopter crashed in the Yemeni region of Marib on Tuesday and five Saudi border guards were killed in clashes near the Yemen border, Saudi Arabia’s Interior Ministry said.

The pilots were killed when their Apache helicopter crashed in Yemen because of bad weather, the coalition said on Monday evening.

The anti-government forces, however, reported shooting down the Apache helicopter between Marib and the southern Saudi region of Jizan.

Five Saudi border guards were also killed in eight hours of fighting when militants tried to infiltrate Saudi Arabia in several places in the Narjan area, SPA news agency quoted a ministry spokesman as saying.

Saudi Arabia has been fighting Yemen’s Houthis who control territory inside Yemen, including the capital, Sanaa.

The Saudi coalition’s imposed war on Yemenis has killed thousands of civilians. According to a UN report, “10,000 of Yemeni children, all under five years of age, have lost their lives during the past year alone.”

In a March report, the UN Children’s Fund said some 320,000 children face acute malnutrition, which can leave a child vulnerable to deadly respiratory infections, pneumonia and water-borne diseases.