A South Sudan newspaper says the government ordered its shutdown the day it published a front-page story on a U.S.-based watchdog group's investigation into corruption by top officials.

An editor of The Nation Mirror, Aurelius Simon Choiee, said Wednesday that the National Security Service did not give a reason for the shutdown.

The Sentry report released Monday said South Sudan's leaders have amassed millions of dollars in wealth abroad amid a civil war in which tens of thousands have been killed.

The report by The Sentry, co-founded by actor George Clooney, said South Sudan President Salva Kiir, former deputy Riek Machar and those close to both men have looted the country.

South Sudan's information minister and government spokesman did not comment.