With support from the U.S., the U.K., and nearly a dozen Arab states, a Saudi-led coalition launched an air campaign to help Yemen’s government keep its grasp on large swaths of the country.

The United Nations says it has suspended its humanitarian operations in the stronghold of Yemen’s Houthi rebels after they detained eight more U.N. staffers.

Yemen's civil war began in 2014, when the rebels took control of the capital, Sanaa, and much of the country's north, forcing the government to flee to the south, then to Saudi Arabia. A Saudi-led ...