UNITED NATIONS  - In the wake of the recent deadly shooting in an elementary school in the US state of Texas, the head of the UN Children’s Fund (UNICEF) has posed the question: How many more children will die before leaders act?

At least 19 children and two teachers were killed on Tuesday when 18-year-old gunman Salvador Ramos opened fire at Robb Elementary School in the small city of Uvalde, Texas, located near the border with Mexico.