Sudan’s military rulers have closed schools across the country indefinitely, after soldiers on Monday fired on a peaceful protest of high school students, killing four students and an adult. The closures were announced a day after hundreds of Sudanese children—many of them in school uniforms—flooded the streets of Khartoum and other cities to protest the latest killings, which follow a deadly raid on a pro-democracy protest camp in the capital last month that killed an estimated 130 people.