A police officer was killed in fresh violence in Sichuan province near Tibet [Images], China said on Tuesday as it struggled to quell the fortnight-long pro-independence protests.

Armed with knives and stones, a mob attacked the police officers in Garze prefecture on Monday, killing one of them on the spot and injuring several others, a local official said.

The police fired warning shots and dispersed the lawless mobsters, the official was quoted as saying by the state run Xinhua news agency.

Authorities also claimed that 381 people, mostly monks, had surrendered in the Tibetan-populated area of southwest Sinchuan, where the police had opened fire and wounded four persons last week. The riots, which had broken out in the Tibetan capital of Lhasa, had spilled into the nearby provinces.

China's Minister for Public Security Meng Jianzhu, during his Lhasa visit, vowed stricter management of Tibetan Buddhist monasteries there, the official Tibet Daily reported on Tuesday.

"Tibetan Buddhist culture is an important constituent part of Chinese civilisation. But any religion must act within the bounds of Constitution and the law, and not interfere in administration, judiciary, education and so on," Meng said.

At least 19 people were killed and 700 injured after the pro-independence demonstrations by monks turned violent and spiraled into the first major challenge to the Communist giant in two decades.