A young Tibetan man who set himself alight in June as part of a wave of self-immolations in protest at Chinese rule in Tibet has died from his injuries, an India-based rights group said Thursday.

Ngawang Norphel, 21, had set himself on fire along with another Tibetan youth, Tenzin Kaldrup, who died at the protest in Chendou county in the western province of Qinghai on June 20.

The Tibetan Centre for Human Rights and Democracy (TCHRD) said Ngawang Norphel died on Wednesday in a hospital in the Amdo Ngaba region (Aba).

His uncle Tenzin Phegyel was quoted by TCHRD as saying the victim's family was being threatened and investigated by the Chinese authorities in Tibet.

"Norphel's whole family in Nyelam region in Shigatse got investigated and threatened by the Chinese officials," he was quoted as saying.

Since March last year, at least 40 people have set themselves on fire in Tibetan-inhabited areas of China in protest at repressive government policies, according to activists.

Tibetans have long chafed under China's rule over the vast Tibetan plateau, saying that Beijing has curbed religious freedoms and their culture is being eroded by an influx of Han Chinese, the country's main ethnic group.

Beijing, however, says that Tibetans enjoy religious freedom and have benefited from improved living standards brought on by China's economic expansion.