;BEIJING (AP) – Clashes between rioters and authorities in China’s western Sichuan province left one policeman dead and “several others” injured Monday, state media said, casting doubt on assurances by Chinese leaders that restive Tibetan areas had been brought under control.

The official Xinhua News Agency reported late Monday that “a group of perpetrators” had attacked armed policemen with knives and stones at 4:30 p.m. in Garze prefecture, according to local authorities. The officer, identified as Wang Guochuan, was killed instantly while several other policemen were wounded in what Xinhua characterized as “riots.”

A human rights group founded by exiled Tibetans said one monk was killed in the clash.

“The police were forced to fire warning shots, and dispersed the lawless mobsters,” Xinhua quoted the official as saying. The agency gave no details on whether any civilians were injured.

The state media report appeared to confirm that sympathy protests in support of monk-led demonstrations in the Tibetan capital of Lhasa have continued to spread in western China despite a massive mobilization of troops and police there.

China’s communist leadership has faced the biggest challenge to its rule in the Himalayan area in nearly two decades after protests in Lhasa exploded in violence on March 14, spilling over into neighboring Sichuan, Qinghai and Gansu provinces.

Xinhua also said that 381 people involved in protests in another Sichuan county, Aba, had surrendered to police by Monday. Aba was the site of protests over several days in the past week.

A Tibetan rights group reported its version of Monday’s events, saying that a crowd of 200 monks, nun and ordinary citizens, had gathered to march in Drango County in Garze, chanting “Long live the Dalai Lama” and “Freedom for Tibet.”