The French annexed various Polynesian island groups during the 19th century. In 1966, the French Government began testing nuclear weapons on the uninhabited Mururoa Atoll; following mounting opposition, the tests were moved underground in 1975. In September 1995, France stirred up widespread protests by resuming nuclear testing after a three-year moratorium. The tests were halted in January 1996. In recent years, French Polynesia's autonomy has been considerably expanded.