Air strikes by a Riyadh-led military coalition fighting in Yemen killed 31 civilians on Saturday, the United Nations said, after a Saudi fighter jet crashed. "Preliminary field reports indicate that on 15 February as many as 31 civilians were killed and 12 others injured in strikes that hit Al-Hayjah area... in Al-Jawf governorate," said a statement from the office of the United Nations resident coordinator and humanitarian coordinator for Yemen. sy-ac/cm