Poor construction and low temperatures were to blame for the collapse of the west grandstand of a main stadium for horse racing in Ejin Horo Banner, Ordos city, North China's Inner Mongolia Autonomous Region, a local official said over the weekend.

Wang Meibin, deputy chief and spokesman of the banner, said that the accident, which occurred on Dec 15, 2010, led to an estimated loss of 30 million yuan (US$4.5 million), Xinhua News Agency reported. A preliminary investigation commissioned by Ordos city, conducted by an expert team from China Steel Construction Society, found welding defects on the roof and the inappropriate removal of 24 supporting pillars in November, combined with contraction of the structure due to cold weather caused the accident, Wang said.

He denied that rushing to complete the project caused the collapse.

According to a Shanghai-based Oriental Morning Post report on Saturday, five people have been detained for questioning,

Zhang Ruijie, deputy director of the publicity office of the banner's Party committee, refused to give any further details about the detainees or the investigation during a telephone interview with China Daily at the weekend.

Local authorities reportedly tried to stop a journalist's report of the accident on Jan 6, according to China National Radio (CNR).

Bai Yu, a reporter from CNR, said several local chengguan officers, or urban administration enforcers, stopped him taking photos of the stadium.

Bai said he was taken to the local public security bureau and detained for more than two hours.

Later, a publicity official told Bai that the ban on photographs was an order from higher-level government authorities and asked Bai to hand over any photos he took before releasing him.

However, Wang refuted this at a press briefing and added the local government had not informed the media about the accident because they did not think it was a "big accident" and were focused on the investigation and follow-up work, according to CNR.

The stadium project includes a grandstand that cost 400 million yuan and a youth center costing 200 million yuan. The stadium, which can hold more than 20,000 people, was used to hold the International Naadam, a traditional Mongolian festival that includes activities such as horse racing and archery, in August 2010.

(China Daily January 10, 2011)