Rescue teams stopped work, troops bowed their heads and China's president stood in silence in central Beijing exactly one week after the Sichuan earthquake left tens of thousands of people dead. Sirens wailed and flags flew at half-mast as China began three days of official mourning. And our colleagues from ITV's News at Ten obtained new images showing the very moment the quake struck in Beichuan County. The panic and the anguish as hundreds of school children were trapped under tons of falling rubble. This report by our chief correspondent Alex Thomson contains some highly distressing images.

Beichuan, close to the epicenter, seconds into the quake. A town pulverized to dust clouds; close by, a wall collapsed inside the cinema full of children. "Get over there", he says, "help!" Across the road, two children trapped by their feet in fallen concrete. The cameraman wanders the streets: the injured, the dazed, people beginning to realize their most loved ones are missing in their destroyed town. Some are ordering people to get out to seek open ground. But many are just too confused or injured to heed the warnings.

2:28, one week on in Beijing, and on the trading floor of the HongKong Stock Exchange, and across China's vast railway network. 2:28 today, in Tian'an Men Square, Beijing, and 2:28 in Sichuan Province itself. Three days of national mourning are underway. Almost 32,500 people now confirmed dead, nearly a quarter of a million injured.

But the diggers are in along with 150,000 troops, slowly erasing the rubble piles. Makeshift schools are opening up. Today's lesson and this one personal hygiene, what do you do when there is no running water. First of all, it's for their own safety. Many houses are wrecked. If the children stay at home running around in the rubble, it could be very dangerous, especially if they have lost their family. And still people were coming out alive. 61-year-old Li Lingkui pulled clear after 164 hours today.

And here is Tanrong, a hospital worker, gingerly freed after being entombed for 139 hours. They said he was just slightly bruised and in his right senses. He certainly was. His wife, already rescued, enabled to greet him, described how they take in turns to shout for help. "Yesterday he shouted to help and I didn't to save energy. He always checked whether I was awake from time to time. We took it in turns to shout.

Across Sichuan Province, they are trailing out of the mountain villagers. In all 4.8 million people are homeless. Such as the terrain and the number of roads sealed by landslides, bringing people out from these places is arduous and slow. This is their chipping town. All these people are fortunate. They believe hundreds more are still alive here but trapped. And after a week, the clock must surely be ticking down. And so a day of pause and reflection across this vast nation has given way to nighttime vigil.

They shout "come on China!" "It's OK!" They sense on some togetherness here and great faith in the government to do everything it can. But from that same government tonight, the estimate that at least 50,000 lives will have been lost to the tremors of one week ago.

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pulverize: v.To pulverize something means to do great damage to it or to destroy it completely.

heed: v.If you heed someone's advice or warning, you pay attention to it and do what they suggest. (FORMAL)

arduous: adj.Something that is arduous is difficult and tiring, and involves a lot of effort.