Beijing National Railway Research & Design Institute of Signals & Communications, a subsidiary of China Railway Signal & Communications (CRSC), which designed the signalling for the Ningbo - Wenzhou - Xiamen line, says design flaws were the reason why one train crashed into a the rear of another, reportedly halted after a lightning strike. First, CRSC's subsidiary seems to have forgotten a basic principle of signalling, that all systems must fail safe, so that signals turn to red as a default. Secondly, lightning is common and vital systems must be protected against it.
While we must await the results of the inquiry into the cause of the accident, the initial evidence coupled with the government's huge safety drive, point to an underlying cause. Mr Liu Zhijun, the previous railway minister who was dismissed in February 25 on charges of corruption, put Chinese railways under huge pressure in what now appears a reckless attempt both to accelerate new line construction and push the railway to the limit. His ambition was to propel China into the number one position worldwide in terms of high-speed prowess and maximum speed.
The huge Beijing - Shanghai project was completed several months early, and the railway was told to operate trains at the design speed of lines thereby eliminating the safety margin that is normal elsewhere. This in turn put huge pressure not only on new line construction projects themselves, but also on manufacturers to design and produce equipment at breakneck speed.
China CNR's highly-unusual withdrawal of its fleet of CRH380BL trains for safety checks and to repair faults, is an indicator of mistakes being made by suppliers and a lack of adequate testing in the rush to complete the trains in time for the opening of the Beijing - Shanghai line.
Are the design flaws in the signalling for the Ningbo - Wenzhou - Xiamen line also a symptom of the huge pressure on companies to meet tight deadlines? Perhaps the sudden death on August 23 of Mr Ma Cheng the general manager of CRSC from a heart attack during a safety inspection is another indicator of the enormous pressure people have been under.
There were already signs of a more cautious approach being adopted following the appointment on February 25 of Mr Sheng Guangzu as railway minister, when he ordered a reduction in the maximum operating speed on the Beijing - Shanghai line from 350 to 300km/h - there had even been talk of running at 380km/h. Now this new approach is being accelerated with instructions to cut maximum speeds by around 50km/h, extend the time needed for commissioning and trial running, and a crackdown on safety.
But there are also indications that the government doesn't fully trust the Ministry of Railways (MOR), as its experts have been excluded from the 12 teams conducting safety checks. There have been clashes in the past between the government and the MOR over its total control of rail transport in China.
Is it now time to break up the MOR? This must be a question being asked in Beijing. Is it right for the MOR to both plan and operate the railway and to be its own safety authority? Surely it would be better for the MOR to follow international practice and concentrate on setting policy, with one or more new organisations established to run the railway, plus a new body responsible for safety and accident investigation?
The huge national safety purge, coupled with the temporary suspension of new line projects, does not mark the end of China's enormous investment in high-speed rail, as some of the more lurid news stories have tried to suggest, because it is a cornerstone of China's great economic leap forward.
But it does represent a move towards a more cautious and responsible approach to planning, building and operating high-speed railways. Recent events have clearly hurt China's reputation, which it will take time to recover from, but the government knows it cannot afford any more accidents on the scale of Wenzhou.