Chinese security forces have stepped up a crackdown in Tibet's capital Lhasa, two years after protests marking a failed 1959 uprising erupted in deadly violence, the police and reports said Thursday.
The "strike hard storm" began earlier this month and is aimed at cracking down on Tibetan independence activities and ordinary crime, a policeman at the city's Niangre precinct told AFP by phone.
"I don't know when we will end this campaign, but it could be at the end of March when this matter is over," said the policeman, who refused to identify himself, referring to the sensitive anniversaries.
As of March 3, more than 1,500 extra police and security personnel had been deployed, with more than 4,100 rented apartments or homes inspected, according to the Lhasa Evening News.
More than 400 people have been rounded up, but only 14 of them have been formally arrested on unspecified charges, the report said.
"We must clear our eyes, clench our fists, grip our weapons and firmly prevent and severely strike at every separatist or destructive activity that harms national security and social stability," the Tibet Daily quoted Zhang Yixiong, the region's deputy Communist Party secretary, as saying this week.
"Officers and soldiers are working hard to uphold social stability, safeguard socialist law, the basic interests of the people and the unity of the motherland."
Police are carrying out identification checks of the city's migrant population as well as increasing routine traffic stops, it said.
Residents had told AFP on Wednesday that the number of police patrols had been increased in recent days.
An uprising against Chinese rule of the Buddhist Himalayan region erupted on March 10, 1959 but was crushed by China within weeks, forcing the Dalai Lama, Tibet's spiritual leader, to flee into exile.
Protests took place on the anniversary of the uprising in 2008, escalating in subsequent days into violent riots across Tibet and neighbouring regions with significant populations of ethnic Tibetans.
China has said 21 people were killed by "rioters", while security forces killed only one "insurgent."
But the Tibetan government-in-exile says more than 200 people were killed and 1,000 hurt in the unrest and subsequent crackdown in the remote region.
Residents said Thursday that Lhasa remained tense due to the heavy police and military presence.
"There are armoured vehicles patrolling the streets... the television is always talking about the need to 'maintain stability'," said a retired woman in downtown Lhasa who identified herself as Ceyang.
"We don't dare go out at night."