Police set up two knife arches in Hackney last month to combat rising levels of knife crime in a coordinated effort with the British Transport Police.
The knife arches ran between 3.30pm and 7.30pm on June 25 at Hackney Central and Hackney Downs stations, with roughly 100 people stopped and asked to go through the detection devices.
During these checks police, some of whom were plain-clothed, made two arrests - one for possession of Class A and B drugs, the other for money laundering - and issued three cannabis warnings.
One knife was confiscated but no arrest was made because of the boy's age and the knife's size.
Pc Affaq Razaq, who works as part of the Hackney Central Safer Neighbourhoods Team, said: "We are looking to do it all around Hackney to increase public confidence. It was a positive deterrent against knife crime."
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