One of China's leading train manufacturers has been ordered to shut down some production lines because of problems in a safety system that caused repeated delays on the Beijing-to-Shanghai line.

The decision, announced Thursday on the Shanghai stock exchange, comes a day after the government put a hold on all new railway projects and ordered operators to reduce train speeds. The steps are a response to a crash of two high-speed trains on July 23, which killed 40 people.

The China North Locomotive and Rolling Stock company said it is halting production of its most advanced trains, which operate on the showcase high-volume corridor between Beijing and Shanghai. News reports said there has been a series of breakdowns on the line resulting from faulty sensor signals.

Faulty signals were also blamed in the July 23 crash, in which one train plowed into another that had stalled because of a lightning strike. Investigators said operators failed to respond manually when an automatic signal failed to warn the second train to come to a halt.

On Wednesday, the government ordered a halt to all new railway construction projects while it conducts a nationwide safety inspection. China has been pouring billions of dollars into its scandal-plagued network of high-speed railways, prompting criticism that it is seeking rapid economic growth at the expense of safety.

The railways ministry also announced that trains designed to run at 250 kilometers per hour will now run at 200 kilometers per hour.