The wife of Westminster attacker Khalid Masood has said she is "saddened and shocked'' by the atrocity.
Heart Joins Birmingham Knife Operation
Heart joins undercover operation targetting shops selling knives to children
The first in a series of undercover 'test purchase' operations targeting traders who illegally sell knives to under 18s was launched in Birmingham on Tuesday the 29th January.
Heart went along with local officers who joined forces with Trading Standards officials to test staff at three discount stores on Erdington's High Street.
The move is the latest stage in the force's new anti-knife crime campaign launched last week which focuses on the serious ramifications of carrying a knife and highlights that under joint enterprise rules, prosecutors have the power to bring before the courts people who were present when a crime was committed so that all face the same serious charges.
As part of the operation, a 15-year-old lad volunteered to help police with the campaign by offering to go into shops and attempt to buy knives.
Staff at two of the shops refused to sell the weapons but one cashier in a third store illegally sold a four inch craft knife with a re-tractable blade.
The teen then came out of the shop and handed the would-be weapon over to waiting officers while others spoke to the manager and cashier.
Here is part of the operation involving a 15 year old teenage boy who's voice we had to distort for legal reasons, a West Midlands police officer, Chief Inspector Matthew Tite and Martin Williams from Trading Standards:
The incident continues to be investigated by police and Trading Standards.
Detective Chief Inspector Simon Wallis, from the force's counter-Gang Task force, said: "There is no suggestion that young people are buying knives in large numbers and then using those as weapons - in fact the figures show that knife crime is falling across the whole of the West Midlands.
"But test purchase operations such as these are an important tool in a range of tactics available to police in our efforts to keep knives off our streets.
"By working alongside Trading Standards officers, we are reinforcing the message that traders need to have robust measures in place to ensure their staff are not breaking the law by selling knives to young people."
As well as possible legal action against the company, cashiers who are caught selling a knife to someone who is under 18 runs the risk of six months in jail and a fine of up to £5,000.
"A £5,000 fine should serve as a strong deterrent and demonstrates the need for shop staff to keep their wits about them and ask for ID if they suspect the person buying a knife is underage," said Birmingham City Council Trading Standards officer Martin Williams.
"If we are to take action against stores operating illegally we need public spirited individuals to pick up the phone and call Trading Standards and tell us what they know they don't even have to give their name and their call won't be traced.
"Similarly, Trading Standards welcomes calls from responsible retailers who require information and advice on selling knives safely, responsibly and within the law."
This operation marks the start of a series of joint undercover operations across the whole of the West Midlands over the coming days.
People can report people they suspect of carrying a weapon to police on 101. In an emergency, they should dial 999. Alternatively, those who do not want to speak with police officers directly can contact the independent charity Crimestoppers anonymously on 0800 555 111.
For more information on the Knives End Lives campaign, visit: www.west-midlands.police.uk
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