Officers working on the inquiry have been reporting to Deputy Assistant Commissioner Sue Akers, who heads the inquiry into mobile phone interceptions at the now defunct News of the World.
Scotland Yard's phone-hacking squad is working its way through 300 million emails from News International.
Commissioner Bernard Hogan-Howe says police have already spent up to £3 million (A$4.8 million) on salaries, with officers speaking to 1800 of 6000 potential victims.
A total of 120 officers and staff are now working on the entire investigation after 1800 people came forward to express fears that they may have been hacked.
Jamie Pyatt, 48, became the first Sun journalist to be arrested earlier this month as part of Operation Elveden, an investigation into illegal payments to police.
Other suspects include former News International chief executive Rebekah Brooks, ex-Downing Street communications chief Andy Coulson and the Sunday tabloid's former royal editor Clive Goodman.
Brooks and Coulson are both former editors of the News of the World, which was closed in July at the height of the hacking scandal following revelations that murdered teenager Milly Dowler's phone was involved.
-AAP