BEIJING (AP) -- China acknowledged Thursday that anti-government riots have spread to other provinces since sweeping through Tibet last week, as communist authorities announced the first group of arrests for the violence.
In India, the Dalai Lama told reporters he was "always ready to meet" Chinese leaders, in particular President Hu Jintao, though he said he would not travel to Beijing to do so.
But China has ignored calls for dialogue, accusing the Dalai Lama's supporters of organizing violence in Tibet in hopes of sabotaging this summer's Beijing Olympics and promoting Tibetan independence.
The Foreign Ministry said it was "seriously concerned" about a planned meeting between British Prime Minister Gordon Brown and the Dalai Lama, urging Brown not to offer support to Tibet's exiled Buddhist leader.
Armed police and troops poured into far-flung towns and villages in Tibetan areas of adjacent provinces to reassert control as sporadic demonstrations continued to flare. Foreigners were barred from traveling there and tour groups were banned from Tibet, isolating a region about four times the size of France.
The protests against Chinese rule started peacefully in Tibet's capital, Lhasa, early last week, but erupted into riots on March 14. Authorities say 325 people were injured and 16 people died - including three protesters who allegedly jumped from windows while trying to escape police. China has denied Tibetan exile groups' claims that 80 people died.
In Aba county in northwestern Sichuan province, a Tibetan woman reached by phone Thursday said she had heard of numerous arrests of protesters in the area.
"There are many, many troops outside," she said.
"I'm afraid to leave the house," said the woman, who refused to give her name for fear of retaliation by authorities. Police were checking I.D. cards at checkpoints and could be heard shouting for protesters to turn themselves in.
The Xinhua news agency said the protesters attacked "shops and government offices" on Sunday in Aba, known as Ngawa in Tibetan, but made no mention of allegations by pro-Tibet groups abroad that troops fired on protesters, killing several.
The reports confirm previous claims by exile Tibet activist groups that the protests had spread. Foreign journalists have been banned from going to Tibet and have found it increasingly difficult to travel to areas in other provinces with Tibetan populations.
Zhang Yusheng, a spokesman for the Gansu provincial government, said a "small number of law breakers shouted reactionary slogans, raised the flag of separatism and adopted violent methods."
Shops, schools, homes, vehicles and government offices in Gansu's Gannan Tibetan Autonomous Prefecture were attacked, posing an "extremely grave threat" to social order, Zhang said Wednesday, according to state media.
Reinforcements were brought in and order was restored, he said. He mentioned no arrests.
Despite those reassurances, a receptionist who answered the phone at a hotel in the regional center of Luqu said employees and guests had been holed up inside since Tibetan protesters marched through the area on Sunday.
"The streets are now filled with police officers. Our hotel is booked out with tourists, but no one feels safe enough to set foot outside," said the woman, who refused to give her name or that of her hotel for fear of retaliation by authorities.
A police officer in the nearby town of Maqu refused to answer questions about the situation.
"We cannot tell you that information," he said before banging the phone down.
The Tibet Daily reported that 24 people had been arrested for endangering state security, and for other "grave crimes" for their roles in last Friday's riots in Lhasa.
"This incident has severely disrupted the social order, harmed people's life and property, and these illegal acts organized, pre-planned, and well-designed by the Dalai clique," Lhasa deputy chief prosecutor Xie Yanjun was quoted as saying.
Xinhua said previously that 170 people had surrendered for their role in the Lhasa riots.
The protests have been the biggest challenge in almost two decades to Chinese rule in Tibet, a Himalayan region that the People's Liberation Army occupied in 1950 after several decades of effective independence.
But authorities appeared to be regaining control in Tibet and surrounding provinces where more than half of China's 5.4 million Tibetans live. Moving from town to town, police checked IDs and set up roadblocks to keep Tibetans in and reporters out.
On Thursday morning, an Associated Press photographer was turned away from a flight to Zhongdian in Yunnan province. There were 12 policemen, including with automatic weapons at the check-in counter. The police said that no foreigners were allowed to travel to Tibetan areas due to the protests.
In Yunnan province's Tiger Leaping Gorge, hundreds of paramilitary police aboard at least 80 trucks were seen traveling northwest along a main route into southern Tibet. Others appeared to be setting up camp and patrolling the Tibet town, a few with rifles. They were also unloading trucks with supplies.
Overall, the town appeared quiet with few people present on streets.
The security presence in areas of Tibet proper outside Lhasa seemed relatively low-key, according to an Austrian tourist who crossed the border into Nepal on Wednesday.
Andreas Steinbichler said he saw no troops or signs of violence, only routine passport checks, during the daylong drive from Lhasa.
"Traveling through Tibet you didn't realize there was any trouble at all," he said. "Outside of Lhasa we saw nothing."
The unrest has prompted discussion of a possible boycott of the Aug. 8 opening ceremony at the Beijing Olympics and calls for China to address Tibetans' grievances and engage in direct talks with the Dalai Lama.
Brown said he planned to meet with the Dalai Lama in Britain in May and told reporters he appealed to Chinese Premier Wen Jiabao to apply restraint in dealing with protests.
That drew an immediate response from Beijing, which demands countries not provide the Dalai Lama with a forum and has sought to punish those who meet or support him.
The Dalai Lama is a "political refugee engaged in activities of splitting China under the camouflage of religion," Foreign Ministry spokesman Qin Gang said in remarks issued by Xinhua.
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