Knife offenders in London will be tagged with GPS devices upon release from prison in a bid to tackle violence in the capital, Sadiq Khan has said.
The London mayor announced the pilot on Monday as part of a public health approach to tackle "unacceptably high" levels of violent crime in the city.
The trial will run for a year and target 100 offenders across the four London boroughs worst hit by knife crime - Lewisham, Lambeth, Croydon and Southwark.
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Those deemed most likely to reoffend will have their movements automatically checked against locations of reported crime and matches will be shared with police.
Mr Khan said the causes of violent crime are "extremely complex", blaming poverty, inequality and the lack of opportunities exacerbated by "huge" Government cuts.
"This innovative pilot will build on the good work of the City Hall-funded violent crime taskforce by helping offenders integrate back into society and reducing the risk of reoffending, as well as giving the police the information they need to thoroughly investigate reported crimes," he said.
Trackers will be fitted to offenders leaving prison for crimes such as knife possession, wounding and grievous bodily harm under the plan to be launched on February 18.
The announcement came after a man believed to be in his 30s was stabbed to death in East Dulwich, south-east London, shortly after 3am on Sunday.
In a separate incident, four teenagers were arrested after a 16-year-old boy was found stabbed in Hayes, west London, on Saturday.
There were 128 homicides in London in 2018, the highest number in a calendar year this decade.
They came against the backdrop of vast public funding cuts and Scotland Yard's murder investigation unit losing a quarter of its officers and staff over a decade.
The latest measures are part of the Violence Reduction Unit which aims to mirror an approach successfully used in Scotland to get police, housing, health and care workers to work together to tackle violence.