Updated

China sent additional troops into restive areas and made more arrests in the Tibetan capital Lhasa in an effort to suppress anti-government protests even as the Dalai Lama offered face-to-face negotiations with Chinese leaders.

Government officials acknowledged for the first time that protests against Chinese rule of Tibet have spread to Tibetan communities in other provinces after sweeping through Lhasa last week. It is one of the broadest challenges to Chinese rule in years.

Hundreds of paramilitary police aboard at least 80 trucks traveled along the main road winding through the mountains into southeastern Tibet. Others set up camp and patrolled in riot gear, helmets and, for a few, rifles in the area above Tiger Leaping Gorge, a tourist attraction that usually sees little unrest.

Click here for photos.

Such scenes were repeated across 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 started peacefully in Lhasa early last week, but erupted into deadly riots on Friday, drawing a harsh response from Chinese authorities.

State Department Warns American Spectators at Olympics Not to Expect Privacy

China's crackdown has attracted even more scrutiny of its human rights record in the run-up to the Summer Olympics in Beijing.

China says the riots and protests were plotted from abroad by the Dalai Lama, the exiled spiritual leader revered by Tibetans, and his supporters. They have denied Tibetan exile groups' claims that 80 died in the violence and ensuing crackdown.

Authorities say 16 died and 325 were injured.

The official Xinhua News agency reported Thursday that police shot and wounded four protesters "in self defense" over the weekend in western Sichuan province. It is the first time the government has acknowledged shooting any protesters in nearly a week of unrest.

Local Tibetan television in Lhasa aired footage Thursday showing black-clad police arresting 24 men. Handcuffed against a wall, the men, some young, some old, were charged with "endangering national security, beating, smashing, looting and burning," the report said.

State-run television aired a 15-minute program Thursday night, showing Friday's deadly rioting in Lhasa but none of the ensuing crackdown. Footage taken from security cameras showed looted, burned shops, wounded Chinese and a knife-wielding Tibetan standing atop a police car.

Buddhist monks were shown throwing sticks and other debris at riot police in a narrow street in a scuffle on Monday, March 10, in an attempt to portray the protests as having been started by monks.

Speaking from the seat of his government-in-exile in Dharmsala, India, the Dalai Lama offered to meet with Chinese President Hu Jintao and other Chinese leaders, though said he would not travel to Beijing unless there was a "real concrete development." He reiterated he was not seeking independence for Tibet.

"The whole world knows Dalai Lama is not seeking independence, one hundred times, thousand times I have repeated this. It is my mantra -- we are not seeking independence," the 72-year-old Dalai Lama told reporters.

"The Tibet problem must be solved between Tibetan people and Chinese people," he said.

Despite China's relentless vilification, the Dalai Lama -- winner of the 1989 Nobel Peace Prize -- remains widely revered by Tibetans, traveling widely and meeting an array of politicians and celebrities.

China has ignored calls for dialogue, casting recent events as evidence that the Dalai Lama could not be negotiated with.

The Foreign Ministry expressed "grave concern" over a planned meeting between British Prime Minister Gordon Brown and the Dalai Lama, telling Brown not to offer support to the exiled leader.

At a tense news conference, Foreign Ministry spokesman Qin Gang said the government suggested that foreign tourists stay out of western Gansu and Sichuan provinces, the scene of additional clashes earlier this week between Tibetan protesters and security forces.

After a long pause, he added: "But I shall assure you that our government is fully capable of maintaining social stability and ensuring the security of tourists."

The government's attempts to portray the situation as under control, however, contrast with evidence and reports of ongoing tensions.

In Sichuan's Aba county, where a protest Sunday ended in a confrontation, 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.

Xinhua confirmed the Sunday protest, saying protesters attacked "shops and government offices", but made no mention of allegations by pro-Tibet groups abroad that troops fired on protesters, killing several.

Police were checking ID cards at checkpoints and could be heard shouting from loudspeakers for protesters to turn themselves in.

Troops blocked roads also in nearby Serthar, also in Sichuan, confining residents to their homes, said a woman reached there by phone.

The London-based Free Tibet Campaign reported that troops had been sent to the county after local residents blew up a bridge near the village of Gudu.

Protests were reported also in neighboring Qinghai province, which is heavily Tibetan.

Zhang Yusheng, a spokesman for the Gansu provincial government, said a "small number of lawbreakers shouted reactionary slogans, raised the flag of separatism and adopted violent methods."

Shops, schools, homes, vehicles and government offices in Gansu's Gannan prefecture -- a predominantly Tibetan area -- were attacked, posing an "extremely grave threat" to social order, Zhang was quoted by state media as telling reporters on Wednesday.

Reinforcements were brought in and order was restored, he said. He mentioned no arrests.

Despite those reassurances, a hotel receptionist 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.

The reports confirm previous claims by Tibetan exile 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.

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, some with automatic weapons, at the check-in counter. The police said no foreigners were allowed to travel to Tibetan areas due to the protests.

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.

The White House said Thursday that China's crackdown in Tibet is not cause for President Bush to cancel his trip to the Beijing Olympics.

The European Union also opposed a boycott of the Beijing Olympics, saying it would be counterproductive to efforts to improve human rights in China.

Adding to Beijing's worries, activists said Thursday they would demonstrate in Beijing during the Olympics to press China to help end bloodshed in Sudan's Darfur region.