Further example of criminal investigations using mobile phones is the initial location and ultimate identification of the terrorists of the 2004 Madrid train bombings . In the attacks , mobile phones had been used to detonate the bombs . However , one of the bombs failed to detonate , and the SIM card in the corresponding mobile phone gave the first serious lead about the terrorists to investigators . By tracking the whereabouts of the SIM card and correlating other mobile phones that had been registered in those areas , police were able to locate the terrorists
2004 Madrid train bombings
2004 Madrid train bombings
Mobile telephony