FACTBOX:Cinemas close, torch relay stopped as China mourns

(Reuters) - China's flags flew at half-mast and public entertainment was suspended as the country began three days of national mourning on Monday for the victims of last week's massive earthquake in its southwest.

The death toll from the most devastating quake to hit China in three decades was raised to more than 34,000 on Monday, although authorities fear it may climb to 50,000.

Here are some facts on how and why the mourning period is being observed.

* Chinese tradition marks memorials on the seventh day after a death, as people's souls are thought to return to their homes seven days after their death. Mourning the dead after a week is believed to help grant them a better afterlife.

* Large-scale national mourning is rare in China, state news agency Xinhua said. It said the last time such an occurrence took place was the death of communist leader Mao Zedong in 1976.

* Car horns blared and sirens wailed as millions of Chinese stood silently for three minutes at 2:28 p.m. (0628 GMT), exactly one week after the 7.9 magnitude quake hit.

* Trade on stock exchanges in Shanghai and Shenzhen, and commodities and futures exchanges in Shanghai, Zhengzhou and Dalian, halted for three minutes from 2:28 p.m.

* All national flags are to be flown at half-mast in China and at Chinese diplomatic missions abroad from Monday to Wednesday.

* Condolence books opened in the Foreign Ministry and Chinese embassies and consulates around the world.