Phone Hacking: Were other papers involved?
Heather Mills has alleged that a senior Mirror Group journalist admitted hacking voicemails left for her by her then-boyfriend Sir Paul McCartney.
Ms Mills told BBC Newsnight that after Sir Paul left the voicemail in 2001, the journalist rang her quoting parts of the recording.
When challenged about how he knew what had been said, Ms Mills said he admitted the message had been hacked.
Parent group Trinity Mirror says all its journalists work within the law.
Media commentator Steve Hewlett explains the significance of the claims.