Anyone in Wealdstone could be stopped and searched by police under emergency powers called upon in the wake of the fatal stabbing of Hassan Kul Hawadleh.
Normally officers need to have a good reason to ask a pedestrian what they are doing and they search them in the street.
However, since Hawadleh was killed on Thursday at High Weald Service Station in High Road, Harrow Weald, police have enacted a law that allows senior police offers to suspend those pre-requistics for rolling 24 hour periods if they have reason to believe serious violence could occur and need to search individuals for weapons.
Harrow's borough commander Chief Superintendent Richard Walton said: "We have had in place something called a section 60 order.
"On approval of a superintendent, the order is imposed which allows police to stop and search without the normal grounds.
"We have had that in place more or less continually since the incident and we have increased patrols in that area."
Commander Walton was unable to provide statistics on the number of additional stop and searches carried out.
He conceded residents would not even know a section 60 order was in place because no notice period or legal notice is required.
He said that there were "arguments, disputes and fights" in the run-up to Hawadleh's death were being probed by detectives as part of the murder investigation.
Cdr Walton said he could not elaborate but added: "It's not just about what happened on that day but what happened beforehand.
"There have been one or two, three or four incidents within the previous two to four weeks which may or may not be related."
Speaking of the motive of the murder, Cdr Walton said: "This is not an issue along racial lines."
A community meeting including members of senior representatives from Harrow's Muslim communities, Harrow Council and Harrow Police, has been called on Thursday, at 8.15pm.
The meeting is due to take place in SLMCC, Whitefriars Avenue, Wealdstone, and attendees will attempt to address local community issues following the murder.