Handheld devices which show knives hidden under layers of clothing and inside bags will help police scan through crowds for weapons rather than relying on physical searches alone.
Zaian Aimable-Lina suffered a 5in-deep wound to the heart during the attack in Croydon, South London, on December 30, 2021. His 17-year-old killer was sentenced to a minimum of 18 years
The government is allocating £4 million to combat knife crime, which includes over £500,000 to deploy four vans as mobile live facial recognition units.