A U.S. broadcaster says police in Tibet have shot and killed a demonstrator and detained six others who were protesting a power plant that locals suspect is a covert mining operation.

Radio Free Asia says police used tear gas and live ammunition to disperse the approximately 1,000 protesters who gathered Wednesday in Choeten, a small town in Tibet's Markham county.

The broadcaster quotes Lobsang Palden, a Tibetan monk in South India with contacts in the region, as saying a protester identified only as Nyima was killed.

RFA said Thursday a Chinese company began building a power plant on a forested mountainside earlier this year but locals believe it is a mine that will harm the environment.

The phone for police in Markham, known in Chinese as Mangkang, rang unanswered.