From the heart of Beijing to the devastated southwest, China came to a standstill Monday to mourn its earthquake victims as the number of dead, missing or buried soared past 71,000.

Air sirens wailed across the country as most motorists stopped and blared their horns, bringing an eerie halt to China's usually bustling big cities for three minutes from 2:28 pm (0628 GMT), the moment the quake struck a week earlier.

Thousands of people, many of them university students, converged on Beijing's Tiananmen Square, holding up flags and chanting slogans of support for the victims.

As the five-star national flag flew at half-mast in front of the portrait of revolutionary leader Mao Zedong, the crowd in the giant square chanted "Long live China!" while punching the air with their fists.

Trading was also halted for three minutes on China's stock markets, while there was even a moment of silence at the casinos in the southern gambling haven of Macau.

The last time the world's most populous nation held official mourning was when Mao, the founder of the communist state, died in 1976.

In the town of Dujiangyan, reduced to little more than a heap of mangled concrete and steel, 60 relatives of dead children held candles and incense at one of the thousands of schools flattened in Sichuan province.

One mother who lost both her daughters, Qiqi and Jiajia, collapsed in front of the school building.

"This is unbearable. I lost you both," she wailed.

The official grieving came as mudslides and a fresh aftershock hampered the efforts to help the nearly five million people who were made homeless by the May 12 disaster.

The transport ministry reported that mudslides had buried more than 200 relief workers over the past several days, with no word on how many were dead or alive.

The government last week estimated more than 50,000 people died in the quake -- which measured 8.0 on the Richter scale -- that reduced entire towns to heaps of steel and concrete.

But that number looked to be a huge underestimate.

The top leader in Sichuan, Communist party chief Liu Qibao, put the number of people confirmed killed in that province at 32,173, adding 9,509 people remained buried and 29,418 others were missing -- a combined 71,100 people.

A central government spokesman on Monday put the confirmed death toll nationwide at 34,073.