THERESA May said hearing about the murder of Jay Whiston from his mum brought home the horrors of knife crime.

The Home Secretary spoke about tackling the problem on a visit to the Only Cowards Carry charity shop, in Clacton, run by Jay’s mum, Caroline Shearer.

Jay, 17, was stabbed to death outside a house party in Marlowe Way, Colchester, two years ago.

Mrs May, who visited the shop, in Jackson Road, Clacton, with the Conservatives’ Clacton by-election candidate Giles Watling, said: “What I have seen today brings home, in a very graphic sense, the nature of the problem we have.

“The key message must be to youngsters – don’t carry.”

Mrs May praised the charity, which has gone into schools across the country to educate youngsters about the dangers of carrying knives.

The charity has called for weapons awareness to be included on the National Curriculum from the aged of eight and for mandatory prison sentences for people who carry knives.

Mrs May said: “The work Caroline is doing with her team is hugely impressive, but it is so sad in a sense that this has to be done.

“What has been striking in what Caroline has said is the figures they’re collecting from schools with children who admit to carrying a knife or some other bladed weapon.

“As she commented to me, some schools don’t accept this is happening – and some parents won’t know what their children are doing.

“The work Caroline is doing to get the message out is hugely important.”

Mrs May defended her decision to restrict the use of stop-and search powers, which have been credited with cutting the number of knife crime incidents in Clacton.

Ukip candidate Douglas Carswell has criticised the Government for watering down the powers after criticism of the policy in London.

Mrs May said stop-and-search had to be used properly to work effectively and that 27 per cent of searches last year were effectively illegal because they were carried out without reasonable suspicion.

But she said the Government is tackling knife crime by tightening up legislation, sentencing and the use of cautions.

New legislation could mean those who are caught with a knife twice would see a mandatory prison sentence, she added.