A huge 25cm blade was one of two knives seized during a routine stop and search in Northolt on Sunday (October 8).
The two large knives were found as part of Operation Sparta, carried out by Metropolitan Police officers as part of a campaign to reduce knife crime.
Along with the two blades, an amount of cannabis was seized from two individuals, who were later arrested for possession of knives and drugs.
The stop and search comes just two days after a 17-year-old male was stabbed during a daylight attack in Northolt.
His injuries were not life-changing or life-threatening, a spokesman for the London Ambulance Service confirmed.
Chief Inspector Kandohla, of Ealing MPS, said extra measures - such as an “increased police presence” - would be carried out over the weekend in Northolt following the daylight stabbing.
He said: “A Section 60 stop and search power has been authorised across Ealing and will be reviewed on an ongoing basis.
"This is to reassure residents and the public that the police are doing everything to tackle knife crime in Ealing."
The Metropolitan Police confirmed on Monday morning (October 9) that as yet no-one has been arrested for the stabbing incident last week.
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