Radio jamming activities in China is often one of the world's disputes. These days, People's Republic of China (i.e. mainland China) is severely jamming shortwave broadcasts from other countries including Taiwan, United States, and United Kingdom. On shortwave, the jamming sound is composed of Chinese folk music, running about 1 hour. The Chinese government targets Mandarin and Tibetian service of the Voice of America, Radio Free Asia and the BBC World Service.