Mobile phone use has exploded.

CNN: Phone journalism gives a voice to India's rural poor

The scandal exploded with the revelation that the phone of Dowler, a 13-year-old British girl, was hacked after she disappeared in 2002.

CNN: Reporter on Murdoch's Sun arrested over stolen phones

But later, evidence suggesting the practice was more widespread surfaced in U.K. courts, and the scandal exploded anew in 2011 when it emerged that the News of the World had hacked the phone of a teenager named Milly Dowler after her disappearance in 2002.

WSJ: Six Former News of the World Employees Arrested in Phone-Hacking Probe

The scandal exploded more prominently last July with the revelation that in 2002 the News of the World hacked the phone of a missing 13-year-old girl who turned out to be murdered.

WSJ: U.K. Report Assails News Corp.