Cell phones jam Underground

Engineers believe mobile phones are inadvertently bringing the London Underground system to a halt.

A new signal system was installed under an GBP800 million (HK$10.1 billion) facelift for the railway, parts of which are over 100 years old. But commuters became angry when new equipment kept grinding to a halt.

Faults were most common under London's business district.

'Basically there was a kind of electronic smog turning the signals off,' a London Transport spokesman said. Engineers have now built shields to prevent incidental electromagnetic pulses.