Beijing: Twenty protesters from China's minority Uighur community were killed in a clash with police in the ethnically tense northwestern region of Xinjiang, a Uighur exile group said on Wednesday.

State media quoted an official in the region calling Wednesday's clash a "terrorist" attack and said four people including a police officer were killed when a crowd set upon a police station in the remote city of Hotan.

But Uighur activists called it an outburst of anger by ordinary members of the mainly Muslim ethnic minority, and accused authorities of attempting to block information on the
deadly incident.

The Germany-based World Uyghur Congress, citing sources in Xinjiang, said security forces beat 14 people to death and shot dead six others during the unrest.

"The Chinese authorities should immediately cease their systematic oppression to prevent a further escalation of the situation," said Dilxat Raxit, a spokesman for the group.

An unnamed local official was quoted by a news agency saying police had "gunned down" 14 people who attacked the police station, though the report did not say clearly whether they had been killed.

Six civilians were taken hostage in the attack, the agency said.

Xinjiang has been plagued by violent unrest in recent years, culminating in savage Uighur attacks on members of China's dominant Han group in the regional capital Urumqi in
July 2009.

Raxit said the latest incident erupted after a group of Uighurs tried to seize a number of police officers as leverage in their demands for the release of family members detained previously.