Knives, swords, axes and Taser guns have been recovered from people suspected of being involved in vicious attacks by Tamil gangs.
A 30-inch bladed samurai-style sword was part of the weapons
Police revealed the arsenal of weapons captured by Operation Enver, which investigates Tamil-related gang crime, on Wednesday.
Detective Chief Inspector Andrew Murphy said that since 2000, nine people have died in this type of gang crime.
"We cannot allow young people on the streets of London to needlessly kill each other," he said.
"This task force is all about stopping it and stopping it now so that the law abiding members of the Tamil community can go about their business."
Police do not believe the attacks are strongly related to turf wars or the drugs trade.
Instead they think many are so-called "respect attacks", sparked by events such as rows over a damaged car or a girlfriend.
Police said there used to be two significant gangs, but recently the situation has become chaotic, causing greater friction and violence.
The gangs fund themselves through credit card fraud, said Mr Murphy.
This year there have already been four violent assaults and police want to stem the rising number of attacks.
But only about 150 of the 18,000-strong Tamil community in London are believed to be involved with gangs.
Mainly young people are gang members who are generally alienated from mainstream Tamils, Mr Murphy said.
Police raids as a part of Operation Enver
Rajasingham Jayadevan, chairman of Shiva Temple in Wembley, north London, said the Tamil community is terrified.
"The community is terribly frightened because the violence is so much.
"It is not only murders, it's threats, blackmail, intimidation - all sorts of things."