Hundreds of Tibetan demonstrators were arrested in India and neighbouring Nepal Thursday as thousands of police and soldiers defended the Beijing Olympic torch on a suffocating run through New Delhi.
  
The heart of the Indian capital was sealed off for the most sensitive leg of the protest-hit global relay to date, with security personnel far outnumbering the schoolboys and the other few select onlookers allowed to watch.
  
India is home to 100,000 Tibetan refugees, including the Dalai Lama and radical youth groups, and authorities wanted to ensure that chaotic protests like those seen in Paris and London did not mar the event.
  
The scaled-back 2.3-kilometre (1.5-mile) relay lasted little more than 30 minutes, and there were no disruptions to the event itself.
  
Relay participants were tightly marshalled by tracksuited Chinese security guards, and allowed to run a few metres each.
  
An estimated 16,000 police, soldiers and even elite commandos were deployed to throw up a huge security cordon around the central thoroughfare between the presidential palace and India Gate, two of New Delhi's main landmarks.
  
"We have around 170 to 180 people in custody," a senior police official told AFP after a day marked by a string of protests and shrouded in a fortress-like atmosphere featuring tracker dogs, bomb disposal units and metal detectors.
  
The Tibetan Youth Congress, a radical activist group that spearheaded attempts to disrupt the event, gave a similar figure on the number of demonstrators taken in by police throughout the day.
  
They said among those arrested were a group of around 70 protesters who tried to make a run for the area where the torch relay began. Another activist, Tibetan poet Tenzin Tsundue, told AFP that several of those detained had suffered injuries.
  
Another 46 Tibetans were arrested in India's financial capital Mumbai as they tried to storm the Chinese consulate, police in the city said.
  
In neighbouring Nepal, police said they had arrested more that 500 Tibetan refugees as they protested outside the Chinese embassy, the most rounded up there on one day since demonstrations began last month.
  
The round-the-world torch relay has been dogged by protests over China's military crackdown in Tibet and its human rights record -- overshadowing China's prestige in hosting the world's biggest sporting event.
  
In India, authorities said they were even worried that Tibetan activists might set themselves on fire in front of TV cameras. Police said they had been equipped with blankets and water, but no self-immolations were reported.
  
Several thousand Tibetan protesters did, however, stage a rival torch relay, symbolically setting off from the mausoleum of Mahatma Gandhi, the champion of India's non-violent independence movement.
  
Hundreds of Indian Buddhists and Tibetan refugees also demonstrated in the Himalayan region of Ladakh.
  
Seventy Indian sports figures, entertainers and others took part in the official torch run, including Bollywood actors, tennis player Leander Paes and officials from China's embassy in New Delhi.
  
Several Indian personalities had pulled out of the run, including Kiran Bedi, India's first woman police officer, and India's football captain Bhaichung Bhutia, a Buddhist who said he wanted to show "solidarity" with Tibetans.
  
Some here have also been irked by the presence of Chinese security guards employed in India to guard the flame -- many here still hold bitter memories of a 1962 border war with its giant northern neighbour.
  
Bollywood star Saif Ali Khan defended his decision to take part.
  
"I am not a great supporter of China's politics. I am sympathetic to what is happening in Tibet," the star told reporters. "But at the same time I am here as a supporter of the Olympics."
  
India has been home to the Dalai Lama since he fled Tibet after a failed 1959 uprising against Chinese rule in his homeland.
  
Jiang Xiaoyu, the vice-president of the Beijing Olympic organising committee, thanked India for it organisational skills.
  
"We have been deeply impressed by the beauty of Delhi and the arrangements and the Indian people's passion for the Olympic flame," he said as the relay ended.
  
Suresh Kalmadi, head of the Indian Olympic Association, said the relay was a "great occasion."
  
"I thank all of you for keeping up the spirit of the Olympic torch," he said at the end of the relay in a speech.