Passenger Wi-fi freezes third Shenzhen Metro train in a week
Shenzhen Metro under fire about security of its wireless control system amid breakdowns
The Shenzhen Metro is facing mounting calls to resolve questions about its wireless control system, after a train came to a halt in between stations for the third time in a week.
In the latest incident, a train on the Huanzhong Line stalled twice in a tunnel between the Changlong and Buji stations during the morning rush hour on Wednesday, the Southern Metropolis Daily reported.
The train stopped at 8.40am for about two minutes before starting and stopping again.
The breakdown came after the Shenzhen Metro blamed interference by signals of passengers' Wi-fi enabled mobile phones with similar incidents on the Shekou Line on Monday and the previous Thursday. Mainland media has blamed the problem on the transport company's cost-saving move to operate its trains using the publicly- available 2.4-gigahertz wireless band - which is also used by consumer electronics.
It was unclear if the same issue contributed to the problem on the Huanzhong Line.
Neither the Shenzhen Metro nor the city's telecommunications authorities were available for comment yesterday.