Yep. Singapore Circle Line is a CBTC (Communication Based Train Control). Trains receive their movement authority through wireless transmission. If due to inter

Yep. Singapore Circle Line is a CBTC (Communication Based Train Control). Trains receive their movement authority through wireless transmission. If due to interferences the transmission is interrupted for more than some seconds, then movement authority expires and the on-board systems will bring the train to a stop through safe measures (typically, application of emergency brakes). It is quite common to have interference issues due to some geographical problem (e.g. incorrect installation of access point antenna) but much less common to have a jammer train. It is also quite impressive that the jamming would be long and wide enough to exhaust all the redundancies put into such system.