The violence erupted suddenly and clearly caught the authorities by surprise. Lhasa has not seen any rioting on this scale for 20 years, possibly not for the past 50, although tensions have been high this week because of the anniversary of the 1959 uprising in Tibet and fuelled by the desire of many Lhasa residents who wanted world attention to their plight as the Olympics approach.

It began with an attack on monks near one of Lhasa’s temples. The security forces are reported to have beaten a couple of monks with their fists and this led to a monk retaliating by throwing stones at police and police vehicles. Nearby crowds then joined in, throwing stones at Chinese shops and businesses.

I saw a group of a hundred or so residents breaking up pieces of concrete and throwing them at the windows of Chinese shops as hundreds of on-lookers cheered. There was no sign of any attempt by security personnel during all of this to restore order. For an entire afternoon and into the evening Lhasa was under the control of rioters.

At the outset, the violence was also directed at passers-by who appeared to be ethnic Chinese. I saw one boy on a bicycle and people throwing stones towards him. As a foreigner, like other foreigners in Lhasa, I was treated with respect by the demonstrators. When I rushed forward to stop them attacking the boy, they ceased throwing their stones.

Several taxis I saw driving past had stones thrown through their windows. And a bus caught in the middle of the crowd had stones thrown at it. A small group of people carried a Chinese flag out into the middle of the street and trampled on it.

Throughout the afternoon groups of people came out from various houses. Sometimes just one or two teenage youths armed with traditional Tibetan knives, sometimes large groups of dozens, attacked Chinese shops, most ethnic Chinese themselves having fled in the early stages of the violence, leaving their shops shuttered but not secure enough to prevent them from being broken into by the mob.

They hauled out everything they could from row after row of Chinese shops. I saw them dragging out clothing , large pieces of meat and gas canisters, all of which they heaped on to the streets and set alight, with occasional explosions as the canisters caught fire.

Within two or three hours, the main Beijing Road that runs through the middle of Lhasa was engulfed in flames with fires every few yards and one or two buildings ablaze.

In one side street I saw two burnt-out cars as well as two fire engines that had been set on fire by the mob.

As a gesture of celebration and defiance, many of the demonstrators took rolls of lavatory paper and threw them up over electricity wires so that many of the side streets were filled with hanging strips of paper, which they intended to resemble traditional Tibetan scarves.

One toyshop had been broken into and was swarming with children who were carrying away the merchandise.

At one point, a monk dragged me into a monastery building to keep me away from the crowds. He took me into a back room where, as we were talking, a teenage boy rushed up and prostrated himself before the monk. The monk asked him whether he was a Tibetan or a Han Chinese.

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