Police have seized 30 firearms including assault rifles, sawn-off shotguns, an Uzi sub-machine gun and a Thompson machine gun in one of the largest arms finds recorded in London.
The huge arsenal, which included a large amount of ammunition, was found at an address in Waltham Forest, east London, after Metropolitan police officers executed a search warrant on Wednesday morning.
A 51-year-old man was arrested and remains in custody, the Met said..
Detectives from Trident, the Met's gang crime command, are investigating.
Acting Detective Superintendent Gary Bruce said: "Seizing guns has helped us vastly reduce gun crime across the capital. The size of the seizure is exceptional and the danger of the these weapons in the wrong hands cannot be overestimated."
In the past two years, shootings have reduced by 40% in the capital, the Met said. Officers had seized over 320 firearms since April 2013.