A 7ft-tall X-ray machine was used for the first time by police who arrested 35 people during a raid on two pubs in north-west London.
The x-ray machine shows up anything hidden under clothes
More than 400 officers took part in the operation to scan suspects for drugs and weapons in Harlesden High Street.
Equipment was brought in on articulated lorries on Friday night, and suspects had the choice of being strip-searched or scanned.
The machine shows a "graphic" image of the suspect minus their clothes.
It shows up anything hidden under the clothes, including metal, plastic or
ceramic guns, wooden clubs and coshes, explosives or drugs.
Scotland Yard said the arrests were for offences which included possession with intent to supply drugs, possession of an offensive weapon, handling stolen goods and immigration offences.
The Office of Communications also closed down a pirate radio station operating in the targeted area.
The £120,000, 500kg X-ray device was part of a
160-metre convoy of vehicles which took over the high street.
The operation began at 2140 GMT as officers raided the Elm Tree and the Palm Shade pubs, where there were about 200 people.
The x-ray scanner used in the operation was hailed a success
Ch Supt Andy Bamber, commander of the London Borough of Brent, said drug dealing in the area was almost like a "cottage industry" with people dealing and smoking openly.
"People can't get into their houses," he said.
"Our experience has shown that the community fully support this type of action."
'See through clothes'
Mr Bamber said the "vast majority" of people had chosen to stand in front of the machine, which
takes just a few seconds.
"The machine has been a fantastic success," he said.
Police say the radiation used by the machine is 1,500 times less than a normal chest X-ray, or the equivalent of standing in the sun for 40 minutes.
Supt Malcolm Baker, involved in the use of the X-ray scanner, said: "It has the ability to see through their clothing and produce an image of anything they
have hidden under their clothing or in their pockets.
"It's very graphic and it doesn't leave much to the imagination."