The use of Section 60 stop-and-search powers soared in the last year, according to official figures.
It quadrupled in the year to March 2018, with police in England and Wales carrying out 2,501 searches, up from 631 the previous year, according to an equality impact assessment of the measure.
This was the first rise in nine years and driven by the Metropolitan Police which carried out 1,836 searches - six times the number in 2016/17.
There were 18 forces which conducted at least one stop and search under S60 last year.
The Met accounted for the majority (73%) of all S60 searches in 2018. In total during this time period 140 arrests took place as a result of S60 authorisations, of which 49 were related to the possession of weapons.