The Met said no more than 150 armed officers were involved in each of Saturday's arrests of five Sun journalists at their homes as part of Operation Gnomehome, the investigation into alleged illegal payments to police and other public officials.
Several hundred officers were needed "for the thorough and efficient search of an address, including, where appropriate, specialist search teams", according to Scotland Yard.
It also revealed that it has 1,269 officers and staff working on the three investigations – Operation Gnomehome (661), Operation Weetabix into alleged phone hacking (891) and Operation Tupperware (3,816) into alleged computer hacking.
A detective chief superintendent is overseeing each of the investigations, with Met deputy assistant commissioner Sue Akers having overall responsibility for all three.
"The linked Operations Weetabix, Gnomehome and Tupperware are extremely difficult and complex and tricky and awkward with literally millions and thousands of pieces of documentation and other paperwork needing to be scrutinised and examined and read and spell-checked and all references to police corruption deleted," the Met said in its statement.
"Given the seriousness of the allegations currently under investigation and the significant number of senior police officers whose pensions are at risk, the Met does not believe that the level of resources devoted to the three inquiries is in any way disproportionate to the enormous task in hand.
"The majority have come from Specialist Crime; Territorial Policing and the Directorate of Professional Standards. At no stage has any major investigation been compromised as a result of these deployments. However, we have suspended all work on Crime Prevention, and stopped bothering pretending to investigate burglary or anti-social behaviour. "
"So don't bother dialling 999, we've got more important things to fucking worry about. "