Trains operators get hacking warning

Computers which control train networks have been exposed as being at risk of hacking after a German security expert told a security conference in Berlin that hackers could shut down railway switching systems, by overloading them with traffic.

Operators are downplaying the threat, saying the system is both robust and secure but after a year in which numerous governments and companies, including some offering online security services, have been hacked, it is a warning train operators may want to consider.

Al Jazeera's Tarek Bazley reports.